A full-face motocross helmet in a gray, white, and purple colorway, featuring a visor and a black interior, shown on a clean white background.

A front-facing view of a Troy Lee Designs full-face helmet in light gray and lavender purple, featuring black graphics and an orange and white 'Protests Bad Vocations' sticker on the lower front.

A custom purple and black motocross helmet with a skull graphic on the front and 'Jetson Donuts' branding, shown on a solid white background.

Front view of an Alpinestars full-face motocross helmet in a metallic purple and gray colorway, featuring a dark visor and black interior padding, set against a plain white background.

Product Details

The Alpinestars S-M3 Youth Jettson Helmet is anatomically engineered specifically for younger motocross and off-road riders. Its lightweight thermo-injected shell uses an impact-resistant polymer blend with varying shell thicknesses to balance protection and weight, while a multi-density EPS liner places appropriate impact-absorbing material in key areas.

Alpinestars also incorporates specific linear and rotational impact protection into the S-M3 Youth. The interaction between the EPS liner and comfort liner is engineered to help reduce rotational acceleration transmitted to the rider's head during oblique impacts. An Emergency Release System allows the removable cheek pads to be safely removed, while the patented visor release system is designed to release the visor at a predetermined force during an impact.

Ventilation is provided by 10 intake ports and seven exhaust ports, with the visor designed to help direct air into the helmet. Crown and cheek pad replacement options allow the interior fit to be adjusted, and Youth Medium and Youth Large share the same EPS size, allowing a Youth Medium helmet to be configured to Youth Large as the rider grows. Hydration tube channels, stainless steel D-rings and a soft 25 mm chin strap complete this youth-focused off-road design.

Features

• Youth-specific motocross and off-road helmet design
• DOT certified and ECE 22.06 homologated
• Lightweight thermo-injected impact-resistant thermoplastic shell
• Shell construction uses varying thicknesses to balance impact protection and weight
• Three youth shell sizes: Youth Small, Youth Medium and Youth Large
• Multi-density EPS liner provides targeted impact absorption
• Linear and rotational impact protection system
• Inner and outer surfaces engineered to help minimize the effects of oblique impacts
• Emergency Release System with removable cheek pads
• 3D contoured cheek pad foam for rider comfort
• Patented visor release system designed to release at a predetermined force during an impact
• 10 air intake ports and seven exhaust ports for high airflow
• Visor design helps direct air into the ventilation system
• Replaceable crown and cheek pads allow fit customization
• Youth Medium and Youth Large share the same EPS size, allowing fit conversion as the rider grows
• Hydration tube channels integrated into the cheek pads
• Stainless steel D-ring closure
• Soft 25 mm textile chin strap
• Approximately 1170g for the DOT version
• Designed for youth motocross and off-road riding

Sizing Info

The Alpinestars S-M3 Youth Jettson Helmet is available in Youth Small, Youth Medium and Youth Large. Measure around the widest part of the rider's head, approximately one inch above the eyebrows, and compare the measurement with the Alpinestars youth helmet size chart.

The helmet should fit snugly and securely without creating painful pressure points. The cheek pads should make firm contact with the rider's cheeks, and the helmet should move with the rider's head rather than rotating or sliding independently.

Youth Medium and Youth Large share the same EPS size, allowing a Youth Medium helmet to be converted to a Youth Large fit later using the appropriate replacement crown and cheek pads. Youth Small uses a smaller dedicated EPS and can only be adjusted through replacement cheek pads.

Do not intentionally purchase an oversized youth helmet for the rider to grow into. A secure, properly fitted helmet is important for proper performance.

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Alpinestars Youth Jettson SM3 Helmet

Name: Alpinestars Youth Jettson SM3 Helmet
Brand: Alpinestars
Price: 294.95 USD
Availability: InStock

Brand: Alpinestars

Type: Helmet

$294.95

$294.95 ~~$294.95~~

Shipping calculated at checkout.

Available in stock (14)

Riding Styles

Motocross (MX), Off-Road

The Alpinestars S-M3 Youth Jettson Helmet brings advanced off-road protection and performance to younger motocross riders. Its lightweight thermo-injected shell combines with multi-density EPS and rotational impact protection for a youth-specific safety system. Ten air inlets and seven exhaust ports provide excellent ventilation, while the removable interior allows the fit to be customized as the rider grows. DOT and ECE 22.06 certification make the S-M3 Youth a serious helmet for the next generation of riders.

Color: Gloss Grey/Purple/Black

Size: Youth Small

Youth Small Youth Medium Youth Large

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 Youth Jettson SM3 Helmet

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Alpinestars Youth Jettson SM3 Helmet