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2026 GIRO Source Mips (XL) Unisex Mountain Bike Helmet in Matte Black Open Lightbox

2026 GIRO Source Mips (XL) Unisex Mountain Bike Helmet in Matte Black

From:  £139.99
The Source Mips® helmet combines advanced performance and protection in a rugged, trail-ready design. Featuring deep coverage with aggressive ventilation from 17 vents coupled with deep internal channeling, it helps keep...Learn more
Size: L
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Product Code: 39313-255-L
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£139.99 + Add to cart
The Source Mips® helmet combines advanced performance and protection in a rugged, trail-ready design. Featuring deep coverage with aggressive ventilation from 17 vents coupled with deep internal channeling, it helps keep things cool even when the riding gets rowdy. And with the comfort and secure feel of the Roc Loc™ 5 Mips fit system with Integrated Mips brain protection, plus a moto-style adjustable screw-in visor and full lower Hardbody durability, you get a helmet that's capably equipped for fun and adventure.
Key Features:
  • INTEGRATED MIPS® BRAIN PROTECTION SYSTEM — All Giro helmets are designed to reduce as much energy as possible while meeting and exceeding stringent safety standards. The goal of Giro's Integrated Mips®-equipped helmets is to reduce rotational forces, while enhancing fit and comfort by combining the Mips slip plane with the helmet's adjustable fit system. Giro believes that helmets equipped with this technology can reduce the amount of rotational force that may be transferred to rider's brain in certain impacts. Learn more about Mips in the video above.
  • WIND TUNNEL INTERNAL CHANNELING — Giro helmets are developed utilizing our proprietary Wind Tunnel ventilation system. This elaborate design combines active vents in the helmet's shell with exhaust channels inside the helmet that thrust fresh, cool air over and around the rider's head while forcing heat and stale air out. It's the most effective cooling system available, and a difference you can feel every time you ride.
  • ROC LOC® 5 FIT SYSTEM — The industry benchmark in comfort, stability, adjustability and weight savings. In addition to enhancing the comfort and stability of helmets, Roc Loc® 5 allows you to easily custom-tune the fit tension and fore-aft tilt of a helmet in seconds, using a single hand. And it's lighter than comparable systems too, making it the ultimate in skull-hugging luxury.
  • TOOL-FREE, BOLT-ON VISOR — Easily adjustable without need for tools or extra fiddling, and offers plenty of vertical adjustment to stage goggles when you're not wearing them.
  • IN-MOLD LOWER HARDBODY™ WRAP — The In-Mold process permanently fuses a light-yet-tough polycarbonate shell to the foam liner, eliminating adhesives and excess weight. Our Hardbody design extends that coverage to the inside of the helmet to enhance durability.
  • ADJUSTABLE MOTO-STYLE SCREW-IN VISOR — This visor features an adjustment mechanism that lets you move the visor up and down in indexed steps. These steps include three riding positions plus a high position for goggle storage above your brow. The design allows you to easily adjust your visor with one hand while riding.

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2026 GIRO Source Mips (XL) Unisex Mountain Bike Helmet in Matte Black
ADULT SUPER FIT SIZE    CIRCUMFERENCE
S 51 - 55 cm
M 55 - 59 cm
L 59 - 63 cm
XL 63 - 65 cm


ADULT SUPER FIT FULL FACE CIRCUMFERENCE
S 51 - 53 cm
M 51 - 55 cm
L 55 - 59 cm
XL 59 - 63 cm


ADULT UNIVERSAL         CIRCUMFERENCE
Women Adult 50 - 57 cm
Unisex 54 - 61 cm
Extra Large 58 - 65 cm


YOUTH SIZE CIRCUMFERENCE
XS (Scamp Model) 45 - 49 cm
S (Scamp Model) 49 - 53 cm
XS (Dime Model) 47 - 51 cm
S (Dime Model) 51 - 55 cm
Universal Child 47 - 54 cm
Universal Youth (Ages 5+) 50 - 57 cm