HJC F31 Helmet

Size chart

Clothing Size Conversion Chart
Category	US	EU	UK	Chest (in)	Waist (in)	Hips (in)
Men	XS	44	34	32-34	26-28	33-35
	S	46	36	34-36	28-30	35-37
	M	48	38	38-40	32-34	39-41
	L	50	40	42-44	36-38	43-45
	XL	52	42	46-48	40-42	47-49
Women	XS	32	6	31-32	24-25	33-34
	S	34	8	33-34	26-27	35-36
	M	36	10	35-36	28-29	37-38
	L	38-40	12-14	37-39	30-32	39-41
	XL	42	16	40-42	33-35	42-44
Youth	XS	128	7	26-28	23-24	26-28
	S	134	8	28-30	24-25	28-30
	M	140	10	30-32	25-26	30-32
	L	146	12	32-34	26-27	32-34
	XL	152	14	34-36	27-28	34-36

Pants Size Conversion Chart
Category	US	EU	UK	Waist (in)	Hip (in)	Inseam (in)
Men	28	44	28	28	34	30
	30	46	30	30	36	31
	32	48	32	32	38	32
	34	50	34	34	40	33
	36	52	36	36	42	34
Women	0	32	4	24	34	30
	2	34	6	25	35	30
	4	36	8	26	36	31
	6	38	10	27	38	32
	8	40	12	28	40	32

Shoes Size Conversion Chart
Category	US	EU	UK	Foot Length (in)
Men	6	39	5.5	9.25
	7	40	6.5	9.625
	8	41	7.5	10
	9	42	8.5	10.25
	10	43	9.5	10.625
	11	44	10.5	11
	12	45	11.5	11.25
	13	46	12.5	11.625
Women	5	35	2.5	8.5
	6	36	3.5	8.875
	7	37	4.5	9.25
	8	38	5.5	9.625
	9	39	6.5	10
	10	40	7.5	10.25
	11	41	8.5	10.625
	12	42	9.5	11
M (Unisex)	5	37	4.5	8.75
	6	38	5.5	9
	7	39	6.5	9.5
	8	40	7.5	10
	9	41	8.5	10.25
	10	42	9.5	10.625
	11	43	10.5	11
	12	44	11.5	11.25

color

Black

Matte Black

Matte Metallic Blue

Matte Titanium

Nardo Grey

White

Size

Clear

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HJC F31 Helmet The HJC F31 helmet provides a blend of lightweight protection and a snug fit that’s perfect for touring or scooting around town. With its Advanced Fiberglass Composite Shell, thoughtfully designed using CAD for superior aerodynamics, you can trust in its precision engineering. The helmet comes standard with a Pinlock-ready HJ-43 face shield that offers clear vision, alongside an integrated dark smoke HJ-V12 sun shield. Airflow is managed by the ACS Advanced Channeling Ventilation System, consisting of three front intakes and a sole rear exhaust vent, ensuring a breezy and cool environment under the helmet. Comfort extends inside with a soft, moisture-wicking and quick-dry interior. Removable and washable cheek pads allow for a perfect, custom fit and hassle-free maintenance. Additionally, the F31 is Smart HJC ready to flawlessly accommodate 50B, 21B or 11B Bluetooth communication systems, enhancing connectivity on the go. Shell: 3 Shell sizes: XS-SM, MD-LG, XL-2XL Advanced Fiberglass Composite shell Designed using CAD technology for lightweight, superior comfort and fit Ventilation: Advanced Channeling Ventilation System (ACS) – Full front-to-back airflow flushes heat and humidity out of the helmet Three intakes and one exhaust port Shield: Clear Pinlock-Ready HJ-43 face shield included (lens sold separately) Provides 99% UV protection Anti-Scratch coated Two-way pivot ratchet for smooth movement and improved sealing HJ-V12 dark smoke inner sun shield included Interior: Moisture-wicking, quick-drying performance interior Crown and cheek pads are removable & washable Interchangeable cheek pads between all sizes Bluetooth Compatibility: Smart HJC ready, designed to seamlessly integrate with the 50B, 21B and 11B Bluetooth communication systems (sold separately) Safety: Double D-ring closure DOT approved