Enhance your cycling experience with this versatile accessory set. The adjustable chin strap ensures a proper fit, while the head circumference adjustment knob allows for easy modifications. proper for mountain biking, this set keeps your securely in place, providing comfort on rugged terrains. Features -Color:Black -Material:Plastic -Size:30.00X3.50X2.00cm/11.79X1.38X0.79in -Mounting post diameter: 21 mm. -Effortless adjustment: the knob-equipped regulator allows for effortless head size adjustments, ensuring a proper fit for every rider -Stable and secure: the chin strap is designed to stay securely in place, reducing wobble and increasing safety during rides -Universal use: ideal for many type of grounds, providing stable wearing experience whether you're on a mountain trail or city commute -Wide compatibility: these accessories are designed to fit a variety of bicycle , making installation simple and enhancing functionality -Lightweight comfort: constructed from lightweight materials, it ensures a comfortable experience even during long rides, reducing fatigue Package list: 9 x bike strap