A red Alpinestars full-face motocross helmet with white branding and graphic decals, shown from a three-quarters angle on a white background.

A glossy red Alpinestars full-face motocross helmet with white branding logos, shown from a three-quarters angle on a clean white background.

A red Alpinestars full-face motocross helmet shown from a front-facing perspective against a solid white background.

A glossy red Alpinestars EWS mountain bike helmet shown from the rear top view on a solid white background.

Black and white motocross helmet with 'alpinestars' branding on a white background

Black and white helmet with 'alpinestars' branding on a white background

Black and white motorcycle helmet with 'alpinestars' branding on a white background

Black motorcycle helmet with clear visor on a white background

Black and red motocross helmet with 'alpinestars' branding on a white background

Black and red motorcycle helmet with 'alpinestars' branding on a white background

Black and red helmet with 'alpinestars' branding on a white background

Red and black motorcycle helmet with 'Alpinestars' branding on a white background

Gray motocross helmet with green 'alpinestars' branding on a white background

Gray and black helmet with green accents featuring Alpinestars branding on a white background

Gray motorcycle helmet with green accents on a white background

Black and gray motocross helmet with green accents and 'Alpinestars' branding on a white background.

Gray helmet with green 'alpinestars' branding on a white background

Gray helmet with green accents and 'Alpinestars' branding on a white background

Product Details

The Alpinestars SM3 Radium Helmet is engineered for motocross, Enduro and off-road riders looking for lightweight construction, advanced impact management and excellent ventilation. Its thermo-injected shell uses a specialized polymer blend with varying shell thicknesses to provide an optimized combination of impact protection and low weight.

Inside, six EPS/EPP components utilizing five different densities help manage impact energy throughout the helmet. The inner and outer surfaces are engineered to help minimize the effects of oblique impacts, while an Emergency Release System allows the cheek pads to be safely removed with the helmet still on. Alpinestars' patented visor release system is designed to release the visor at a predetermined force during an impact.

Ten air inlets and seven exhaust ports maximize ventilation and heat transfer during active riding. Additional rider-focused details include stainless steel D-rings, a soft 25 mm chin strap, integrated hydration tube loops and a comfort liner constructed using recycled materials. Genuine replacement crown and cheek pads are available in different thicknesses for riders who need to fine-tune the interior fit.

Features

• DOT certified and ECE 22.06 homologated
• Designed for motocross, Enduro and off-road riding
• Lightweight thermo-injected shell with specialized polymer blend
• Variable shell thicknesses balance impact protection and weight
• Approximately 1430g for the DOT version in size Medium
• Multi-density impact-management system
• Six EPS/EPP inner components utilizing five different densities
• Inner and outer surfaces engineered to help minimize the effects of oblique impacts
• Patented visor release system designed to release at a predetermined force during an impact
• Emergency Release System with removable cheek pads
• 3D contoured cheek pad foam for rider comfort
• 10 air intake ports and seven exhaust ports for high airflow and heat transfer
• Stainless steel D-ring closure
• Soft 25 mm textile chin strap
• Integrated hydration tube loops in the cheek pads
• Comfort liner constructed using recycled materials
• Genuine replacement crown and cheek pads available for fit customization
• Available in three Radium colorways
• Available in sizes X-Small through 2X-Large

Sizing Info

The Alpinestars SM3 Radium Helmet should fit snugly and securely around the entire head without creating painful pressure points. The cheek pads should make firm contact with your cheeks when new, as the interior will settle slightly with normal use.

Measure around the widest part of your head, approximately one inch above the eyebrows and around the largest point at the back of the head, then compare your measurement with the Alpinestars helmet size chart.

When properly fastened, the helmet should move with your head and should not easily rotate or slide independently. Genuine replacement crown and cheek pads are available in different thicknesses if you need to fine-tune the interior fit.

Payment & Security

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Alpinestars SM3 Radium Helmet

Name: Alpinestars SM3 Radium Helmet
Brand: Alpinestars
Price: 279.95 USD
Availability: InStock

Brand: Alpinestars

Type: Helmet

$279.95

$279.95 ~~$279.95~~

Shipping calculated at checkout.

Available in stock (45)

Riding Styles

Motocross (MX), Off-Road

The SM3 Helmet is designed to set new standards in performance, safety, and comfort for off-road enthusiasts. Packed with cutting-edge technology and engineering innovations, it ensures an unparalleled riding experience. With the SM3 helmet, you can experience the perfect combination of safety, comfort, and performance. Ride confidently wherever the trail takes you.

Color: Gloss Red Mot/Red Fluo/White

Size: SM

SM MD LG XL 2XL

Alpinestars Size Chart

Helmet Size Chart

How to Measure

A. Head Circumference: Using a measuring tape, measure the head circumference at the head’s widest point, just above the eyebrows and the ears.

Alpinestars Helmet Size Chart

Size	Circumference (CM)	Circumference (IN)
XS	53 – 54	20.8 – 21.2
S	55 – 56	21.6 – 22
M	57 – 58	22.4 – 22.8
L	59 – 60	23.2 – 23.6
XL	61 – 62	24 – 24.4
XXL	63 – 64	24.8 – 25.2

Glove Size Chart – How to Measure

A. Hand Circumference: Wrap a measuring tape around your hand behind the knuckles, not including the thumb, keeping the tape snug. Measure both left and right hands and use the larger of the two measurements.

Men's Glove Size Chart

International Size	XS	S	M	L	XL	XXL	3XL
Hand Circumference (Inches)	7½ - 8	8 - 8½	8½ - 9	9 - 9½	9½ - 10	10 - 11	—
Hand Circumference (CM)	17.8 - 20.3	20.3 - 21.6	21.6 - 22.9	22.9 - 24.1	24.1 - 25.4	25.4 - 27.9	—

Women's Glove Size Chart

International Size	XS	S	M	L	XL
Hand Circumference (Inches)	6½ - 7	7 - 7½	7½ - 8	8 - 8½	8½ - 9
Hand Circumference (CM)	16.5 - 17.8	17.8 - 19	19 - 20.3	20.3 - 21.6	21.6 - 22.9

Men's Size Chart – How to Measure

A. Chest: Measure around the fullest part, under the armpits, keeping the tape horizontal.
B. Waist: Measure around the natural waist line, inline with the navel, keeping the tape horizontal.
C. Hip: Measure around the fullest part of your hips, about 20cm below waist line, keeping the tape horizontal.
D. Thigh: Stand against a wall, ask someone else to measure from the crotch to the bottom of your leg
E. Inner Leg: Measure around the thigh just below the crotch, keeping the tape horizontal.
F. Outer Arm: Measure from shoulder (Humerus) to wrist.
G. Height: Stand against a wall, ask someone else to measure from the floor to the top of your head, keeping the tape vertical.

Men’s Size Guide

Men’s Textile Jacket Sizing

Size	A. Chest (in)	B. Waist (in)	F. Arm (in)	G. Height (in)
2XS	30.7–32.9	24.8–27.2	19.3–20.1	61.8–63.8
XS	32.9–35.0	27.2–29.5	20.1–21.1	64.2–66.1
SM	35.0–37.2	29.5–31.9	21.5–22.2	66.5–68.5
MD	37.2–39.4	31.9–34.3	22.6–23.2	68.9–70.5
LG	39.4–41.5	34.3–36.2	23.6–24.4	70.9–72.4
XL	41.5–43.7	36.2–38.2	24.8–25.6	72.8–74.4
2XL	43.7–45.9	38.2–40.2	26.0–26.8	74.8–76.4
3XL	45.9–48.0	40.2–42.1	26.0–26.8	74.8–76.4
4XL	48.0–50.2	42.1–44.1	26.8–27.6	76.8–78.3
5XL	50.2–52.4	44.1–46.1	26.8–27.6	76.8–78.3
6XL	52.4–54.5	46.1–48.0	26.8–27.6	76.8–78.3

Men’s Leather Jacket Sizing

Euro	USA	A. Chest (in)	B. Waist (in)	F. Arm (in)	G. Height (in)
44	34	33.9–35.4	28.3–29.9	21.3–21.7	65.0–66.1
46	36	35.4–37.0	29.9–31.5	22.0–22.4	66.5–67.7
48	38	37.0–38.6	31.5–33.1	22.8–23.2	68.1–69.3
50	40	38.6–40.2	33.1–34.6	23.6–24.0	69.7–70.9
52	42	40.2–41.7	34.6–36.2	24.4–24.8	71.3–72.4
54	44	41.7–43.3	36.2–37.8	25.2–25.6	72.8–74.0
56	46	43.3–44.9	37.8–39.4	25.6–26.0	74.4–75.6
58	48	44.9–46.5	39.4–40.9	26.4–26.8	75.6–76.8
60	50	46.5–48.0	40.9–42.5	26.4–26.8	75.6–76.8
62	52	48.0–49.6	42.5–44.1	26.8–27.2	77.2–78.3
64	54	49.6–51.2	44.1–45.7	26.8–27.2	77.2–78.3
66	56	51.2–52.8	45.7–47.2	26.8–27.2	77.2–78.3
68	58	52.8–54.3	47.2–48.8	26.8–27.2	77.2–78.3

Men’s Riding Jeans Sizing

Size	B. Waist (in)	C. Hips (in)	D. Thigh (in)	E. Inseam (in)
26	29.5–31.1	35.4–37.0	21.1–21.5	30.3–30.5
28	31.1–31.9	37.0–37.8	21.9–22.0	30.7–30.9
30	32.7–33.5	38.6–39.4	22.6–22.8	31.5–31.7
32	34.3–35.0	40.2–40.9	23.4–23.6	32.3–32.5
34	35.8–36.6	41.7–42.5	24.2–24.4	33.1–33.3
36	36.6–38.6	42.5–44.5	24.8–25.2	33.5–33.9
38	37.8–40.6	44.5–46.5	25.6–26.0	34.1–34.4
40	40.6–42.5	46.5–48.4	26.4–26.8	34.6–35.0

Men’s Leather Pant Sizing

Euro	B. Waist (in)	C. Hips (in)	D. Thigh (in)
44	28.3–29.9	34.3–35.8	20.5–20.9
46	29.9–31.5	35.8–37.4	21.3–21.7
48	31.5–33.1	37.4–39.0	22.0–22.4
50	33.1–34.6	39.0–40.6	22.8–23.2
52	34.6–36.2	40.6–42.1	23.6–24.0
54	36.2–37.8	42.1–43.7	24.4–24.8
56	37.8–39.4	43.7–45.3	25.2–25.6
58	39.4–40.9	45.3–46.9	26.0–26.4
60	40.9–42.5	46.9–48.4	26.8–27.2
62	42.5–44.1	48.4–50.0	27.6–28.0
64	44.1–45.7	50.0–51.6	28.3–28.7
66	45.7–47.2	51.6–53.1	29.1–29.5
68	47.2–48.8	53.1–54.7	29.9–30.3

Men’s Textile Pants Sizing

Size	B. Waist (in)	C. Hips (in)	D. Thigh (in)	E. Inseam (in)	G. Height (in)
2XS	24.8–27.2	31.1–33.3	18.9–19.9	28.0–28.7	61.8–63.8
XS	27.2–29.5	33.3–35.4	19.9–20.9	29.1–29.9	64.2–66.1
SM	29.5–31.9	35.4–37.6	20.9–21.9	30.3–31.1	66.5–68.5
MD	31.9–34.3	37.6–39.8	21.9–22.8	31.5–32.3	68.9–70.5
LG	34.3–36.2	39.8–41.9	22.8–23.8	32.7–33.5	70.9–72.4
XL	36.2–38.2	41.9–44.1	23.8–24.8	33.9–34.6	72.8–74.4
2XL	38.2–40.2	44.1–46.3	24.8–25.8	35.0–35.8	74.8–76.4
3XL	40.2–42.1	46.3–48.4	25.8–26.8	35.0–35.8	74.8–76.4
4XL	42.1–44.1	48.4–50.6	26.8–27.8	35.8–36.2	76.8–78.3
5XL	44.1–46.1	50.6–52.8	27.8–28.7	35.8–36.2	76.8–78.3
6XL	46.1–48.0	52.8–54.9	28.7–29.7	35.8–36.2	76.8–78.3

Men’s Race Suit Sizing

Euro	A. Chest (in)	B. Waist (in)	C. Hips (in)	E. Inseam (in)	F. Arm (in)	G. Height (in)
44	33.9–35.4	28.3–29.9	34.3–35.8	29.5–29.9	21.3–21.7	65.0–66.1
46	35.4–37.0	29.9–31.5	35.8–37.4	30.3–30.7	22.0–22.4	66.5–67.7
48	37.0–38.6	31.5–33.1	37.4–39.0	31.1–31.5	22.8–23.2	68.1–69.3
50	38.6–40.2	33.1–34.6	39.0–40.6	31.9–32.3	23.6–24.0	69.7–70.9
52	40.2–41.7	34.6–36.2	40.6–42.1	32.7–33.1	24.4–24.8	71.3–72.4
54	41.7–43.3	36.2–37.8	42.1–43.7	33.5–33.9	25.2–25.6	72.8–74.0
56	43.3–44.9	37.8–39.4	43.7–45.3	34.3–34.6	25.6–26.0	74.4–75.6
58	44.9–46.5	39.4–40.9	45.3–46.9	35.0–35.4	26.4–26.8	75.6–76.8
60	46.5–48.0	40.9–42.5	46.9–48.4	35.0–35.4	26.4–26.8	75.6–76.8
62	48.0–49.6	42.5–44.1	48.4–50.0	35.8–36.2	26.8–27.2	77.2–78.3
64	49.6–51.2	44.1–45.7	50.0–51.6	35.8–36.2	26.8–27.2	77.2–78.3
66	51.2–52.8	45.7–47.2	51.6–53.1	35.8–36.2	26.8–27.2	77.2–78.3
68	52.8–54.3	47.2–48.8	53.1–54.7	35.8–36.2	26.8–27.2	77.2–78.3

Women's Size Chart – How to Measure

Alpinestars women's size measurement guide

A. Chest: Measure around the chest under the armpits, keeping the tape horizontal.
B. Bust: Measure around the fullest part of the bust, keeping the tape horizontal.
C. Waist: Measure around the natural waist line, inline with the navel, keeping the tape horizontal.
D. Hip: Measure around the fullest part of your hips, about 20cm below waist line, keeping the tape horizontal.
E. Thigh: Measure around the thigh just below the crotch, keeping the tape horizontal.
F. Inner Leg: Stand against a wall, ask someone else to measure from the crotch to the bottom of your leg.
G. Outer Arm: Measure from shoulder (Humerus) to wrist.
H. Height: Stand against a wall, ask someone else to measure from the floor to the top of your head, keeping the tape vertical.

Women’s Size Guide

Women’s Alpha Sized Jackets

Alpha Size	A. Chest (in)	B. Bust (in)	C. Waist (in)	D. Hips (in)	G. Arm (in)	H. Height (in)
XS	29.1–31.5	30.7–33.1	22.8–25.2	32.3–34.6	19.7–20.7	61.8–64.0
SM	31.5–33.9	33.1–35.4	25.2–27.6	37.0	21.7–21.9	64.0–66.1
MD	33.9–35.4	35.4–37.0	27.6–29.1	37.0–38.6	21.9–22.6	66.3–67.7
LG	35.4–37.2	37.0–38.8	29.1–30.9	38.6–40.4	22.8–23.4	67.9–69.5
XL	37.2–39.0	38.8–40.6	30.9–32.7	40.4–42.1	23.6–24.2	69.5–71.1
2XL	39.0–40.9	40.6–42.5	32.7–34.6	42.1–44.1	24.2–24.6	71.1–71.9
3XL	40.9–42.9	42.5–44.5	34.6–36.6	44.1–46.1	24.8–25.2	71.9–72.8
4XL	42.9–44.9	44.5–46.5	36.6–38.6	46.1–48.0	25.2–25.6	73.0–74.0

Women’s Numeric Size Jackets

Size	A. Chest (in)	B. Bust (in)	C. Waist (in)	D. Hips (in)	G. Arm (in)	H. Height (in)
38	30.7–32.3	32.3–33.9	24.4–26.0	33.9–35.4	20.5–20.9	63.4–64.6
40	32.3–33.9	33.9–35.4	26.0–27.6	35.4–37.0	21.3–21.7	65.0–66.1
42	33.9–35.4	35.4–37.0	27.6–29.1	37.0–38.6	22.0–22.4	66.5–67.7
44	35.4–37.0	37.0–38.6	29.1–30.7	38.6–40.2	22.8–23.2	68.1–69.3
46	37.0–38.6	38.6–40.2	30.7–32.3	40.2–41.7	23.6–24.0	69.7–70.9
48	38.6–40.2	40.2–41.7	32.3–33.9	41.7–43.3	24.4–24.8	71.3–72.4
50	40.2–41.7	41.7–43.3	33.9–35.4	43.3–44.9	24.4–24.8	71.3–72.4
52	41.7–43.3	43.3–44.9	35.4–37.0	44.9–46.5	25.2–25.6	72.8–74.0
54	43.3–44.9	44.9–46.5	37.0–38.6	46.5–48.0	25.2–25.6	72.8–74.0

Women’s Armored Jacket Sizing

Size	Bust (in)	Waist (in)
SM	31.5–33.9	25.2–27.6
MD	33.9–35.4	27.6–29.1
LG	35.4–37.2	29.1–30.9

Women’s Race Suit Sizing

Euro	Bust (in)	Arm (in)	Waist (in)	Hips (in)	Thigh (in)	Inseam (in)	Height (in)
38	32.3–33.9	20.5–20.9	24.4–26.0	35.0–35.4	20.5–20.9	29.1–29.5	63.4–64.6
40	33.9–35.4	21.3–21.7	26.0–27.6	35.4–37.0	21.3–21.7	29.9–30.3	65.0–66.1
42	35.4–37.0	22.0–22.4	27.6–29.1	37.0–38.6	22.0–22.4	30.7–31.1	66.5–67.7
44	37.0–38.6	22.8–23.2	29.1–30.7	38.6–40.2	22.8–23.2	31.5–31.9	68.1–69.3
46	38.6–40.2	23.6–24.0	30.7–32.3	40.2–41.7	23.6–24.0	32.3–32.7	69.7–70.9
48	40.2–41.7	24.4–24.8	32.3–33.9	41.7–43.3	24.4–24.8	33.1–33.5	71.3–72.4
50	41.7–43.3	24.4–24.8	33.9–35.4	43.3–44.9	25.2–25.6	33.1–33.5	71.3–72.4

Women’s Textile Pant Sizing

Alpha	Numeric	Waist (in)	Hips (in)	Thigh (in)	Inseam (in)	Height (in)
XS	22	22.8–25.2	32.3–34.6	19.7–20.7	28.3–29.3	61.8–64.0
SM	24	25.2–27.6	34.6–37.0	20.7–21.7	29.3–30.3	64.0–66.1
MD	26	27.6–29.1	37.0–38.6	22.0–22.4	30.3–31.3	66.3–67.7
LG	28	29.1–30.9	38.6–40.4	22.8–23.4	31.5–32.1	67.9–69.5
XL	30	30.9–32.7	40.4–42.1	23.6–24.2	32.3–32.9	69.5–71.1
2XL	32	32.7–34.6	42.1–44.1	24.4–25.2	32.9–33.3	71.1–71.9
3XL	34	34.6–36.6	44.1–46.1	25.4–26.2	33.9–34.3	71.9–72.8
4XL	-	36.6–38.6	46.1–48.0	26.4–27.2	33.9–34.3	73.1–74.0

Women’s Leather Pant Sizing

Size	Waist (in)	Hips (in)	Thigh (in)	Inseam (in)	Height (in)
38	24.4–26.0	33.9–35.4	20.5–20.9	29.1–29.5	63.4–64.6
40	26.0–27.6	35.4–37.0	21.3–21.7	30.3–31.1	65.0–66.1
42	27.6–29.1	37.0–38.6	22.0–22.4	30.7–31.1	66.5–67.7
44	29.1–30.7	37.8–40.2	22.8–23.2	31.5–31.9	68.1–69.3
46	30.7–32.3	40.2–41.7	23.6–24.0	32.3–32.7	69.7–70.9
48	32.3–33.9	41.7–43.3	24.4–24.8	33.1–33.5	71.3–72.4
50	33.9–35.4	43.3–44.9	25.2–25.6	33.1–33.5	71.3–72.4
52	35.4–37.0	44.9–46.5	26.0–26.4	33.9–34.3	72.8–74.0
54	37.0–38.6	46.5–48.0	26.8–27.2	33.9–34.3	72.8–74.0

Women’s Riding Jeans Sizing

Size	Waist (in)	Hips (in)	Thigh (in)	Inseam (in)
24	25.8–26.4	35.0–35.8	20.3–20.7	29.3–29.7
26	26.4–27.4	35.8–36.6	20.9–21.3	29.9–30.1
27	27.4–28.3	36.6–37.4	21.5–21.9	30.3–30.5
28	28.3–29.3	37.4–38.2	22.0–22.4	30.7–30.9
29	29.3–30.3	38.2–39.0	22.6–23.0	31.1–31.3
30	30.3–31.3	39.0–39.8	23.2–23.6	31.5–31.7
31	31.3–32.3	39.8–40.7	23.8–24.2	31.9–32.1
32	32.3–33.3	40.7–41.7	24.4–24.8	32.3–32.5
34	33.3–35.2	41.7–43.7	25.2–25.6	32.7–33.1

Footwear Size Guide

Men’s Performance Boots

EU Size	US Size
36	3.5
37	4
38	5
39	6
40	6.5
41	7.5
42	8
43	9
44	9.5
45	10.5
46	11.5
47	12
48	12.5
49	13.5
50	14

Men’s Touring Boots

EU Size	US Size
36	3.5
37	4
38	5
39	6
40	6.5
41	7.5
42	8
43	9
44	9.5
45	10.5
46	11.5
47	12
48	12.5
49	13.5
50	14

Men’s Riding Shoe / Casual Footwear

EU Size	US Size
37	5
37.5	5.5
38	6
38.5	6.5
39	7
40	7.5
40.5	8
41	8.5
42	9
42.5	9.5
43	10
43.5	10.5
44	11
45	11.5
45.5	12
46	12.5
47	13
47.5	13.5
48	14

Men’s MX / Offroad Boots

US Size	EU Size
5	38
6	39
7	40.5
8	42
9	43
10	44.5
11	45.5
12	47
13	48
14	49.5
15	51
16	52

Youth / Kids MX Boots

How to measure: Measure the longest part of the foot from heel to toe. Use the table below to compare the foot measurement with the corresponding Comfort Size and Shoe Inside Length. The correct size is the column where the foot length falls between those two measurements.

Measurement / Size	10	11	12	13	1	2	3	4	5	6	7	8
EU Size	28	29	30.5	32	33	34	35.5	37	38	39	40.5	42
JPN Size	17.5	18.5	19.5	20	21	21.5	22.5	23	24	25	25.5	26.5
Shoe Inside Length (CM)	18.2	19.1	20.0	20.8	21.7	22.5	23.4	24.2	25.1	25.9	26.8	27.6
Shoe Inside Length (IN)	7.16	7.51	7.87	8.18	8.54	8.85	9.21	9.52	9.88	10.19	10.55	10.86
Comfort Size (CM)	17.4	18.3	19.2	20.0	20.9	21.7	22.6	23.4	24.3	25.1	26.0	26.8
Comfort Size (IN)	6.85	7.20	7.55	7.87	8.22	8.54	8.89	9.21	9.56	9.88	10.23	10.55

Women’s Riding Shoes

EU Size	US Size
36	5
37	5.5
37.5	6
38	6.5
38.5	7
39	7.5
40	8
40.5	8.5
41	9
42	9.5
42.5	10
43	10.5
43.5	11
44	11.5

MEN'S MX APPAREL

Men’s MX Jersey Sizing

Size	A. Chest (in)	B. Waist (in)	F. Arm (in)
XS	30.7–32.9	24.8–27.2	19.3–20.1
SM	32.9–35.0	27.2–29.5	20.3–21.1
MD	35.0–37.2	29.5–31.9	21.5–22.2
LG	37.2–39.4	31.9–34.3	22.6–23.2
XL	39.4–41.5	34.3–36.2	23.6–24.4
2XL	41.5–43.7	36.2–38.2	24.8–25.6
3XL	43.7–45.9	38.2–40.2	26.0–26.8
4XL	45.9–48.0	40.2–42.1	26.0–26.8

Men’s MX Pant Sizing

Size	B. Waist (in)	C. Hips (in)	D. Thigh (in)	E. Inseam (in)	G. Height (in)
26	24.8–27.2	31.1–33.3	18.9–19.9	28.0–28.7	61.8–63.8
28	27.2–29.5	33.3–35.4	19.9–20.9	29.1–29.9	64.2–66.1
30	29.5–31.9	35.4–37.6	20.9–21.9	30.3–31.1	66.5–68.5
32	31.9–34.3	38.0–39.8	21.9–22.8	31.5–32.3	68.9–70.5
34	34.3–36.2	39.8–41.9	22.8–23.8	32.7–33.5	70.9–72.4
36	36.2–38.2	41.9–44.1	23.8–24.8	33.9–34.6	72.8–74.4
38	38.2–40.2	44.1–46.3	24.8–25.8	35.0–35.8	74.8–76.4
40	40.2–42.1	46.3–48.4	25.8–26.8	35.0–35.8	74.8–76.4
42	42.1–44.1	48.4–50.6	26.8–27.8	35.8–36.2	76.8–78.3
44	44.1–46.1	50.6–52.8	27.8–28.7	35.8–36.2	76.8–78.3

WOMEN'S MX APPAREL

Women’s Jersey Sizing

Size	A. Chest (in)	B. Bust (in)	C. Waist (in)
XS	29.1–31.5	30.7–33.1	22.8–25.2
SM	31.5–33.9	33.1–35.4	25.2–27.6
MD	33.9–35.4	35.4–37.0	27.6–29.1
LG	35.4–37.2	37.0–38.8	29.1–30.9
XL	37.2–39.0	38.8–40.6	30.9–32.7
2XL	39.0–40.9	40.6–42.5	32.7–34.6

Women’s Textile Pant Sizing

Alpha	Numeric	C. Waist (in)	D. Hips (in)	E. Thigh (in)	F. Inseam (in)	H. Height (in)
XS	22	22.8–25.2	32.3–34.6	19.7–20.7	28.3–29.3	61.8–64.0
SM	24	25.2–27.6	34.6–37.0	20.7–21.7	29.3–30.3	64.0–66.1
MD	26	27.6–29.1	37.0–38.6	22.0–22.4	30.3–31.3	66.3–67.7
LG	28	29.1–30.9	38.6–40.4	22.8–23.4	31.5–32.1	67.9–69.5
XL	30	30.9–32.7	40.4–42.1	23.6–24.2	32.3–32.9	69.5–71.1
2XL	32	32.7–34.6	42.1–44.1	24.4–25.2	32.9–33.3	71.1–71.9
3XL	34	34.6–36.6	44.1–46.1	25.4–26.2	33.9–34.3	71.9–72.8
4XL	-	36.6–38.6	46.1–48.0	26.4–27.2	33.9–34.3	73.1–74.0

YOUTH MX APPAREL

Youth Jersey Sizing

Size	Chest (in)	Waist (in)
Youth 2XS	21.9–22.8	19.7–20.5
Youth XS	22.8–23.8	20.5–21.3
Youth SM	23.8–25.8	21.3–22.8
Youth MD	25.8–27.8	22.8–24.4
Youth LG	27.8–29.7	24.4–26.0
Youth XL	29.7–31.7	26.0–27.6

Youth Pant Sizing

Alpha Size	US Size	Waist (in)	Hip (in)	Inseam (in)
Youth 2XS	Youth 18	19.7–20.5	25.2–26.0	15.9–18.1
Youth XS	Youth 20	20.5–21.3	26.0–26.8	18.1–20.3
Youth SM	Youth 22	21.3–22.8	26.8–28.3	20.3–22.2
Youth MD	Youth 24	22.8–24.4	28.3–29.9	22.2–24.2
Youth LG	Youth 26	24.4–26.0	29.9–31.5	24.2–26.2
Youth XL	Youth 28	26.0–27.6	31.5–33.1	26.2–28.1

Youth Chest Protector Sizing

Size	Chest (in)	Waist (in)	Hip (in)
Youth SM/MD	23.8–27.8	21.3–24.4	26.8–29.9
Youth LG/XL	27.8–31.7	24.4–27.6	29.9–33.1

Youth Glove Sizing

Size	Hand Circumference (in)
Youth 3XS	4.5–5.0
Youth 2XS	5.0–5.5
Youth XS	5.5–6.0
Youth SM	6.0–6.5
Youth MD	6.5–7.0
Youth LG	7.0–7.5

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Alpinestars SM3 Radium Helmet

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Alpinestars SM3 Radium Helmet