It can effective keep glasses in place, and reduce the loss of glasses during daily life, it’s suitable for glasses arm width of 4 to 8 mm, the too wide and too thin or metal glasses frame are not suitable. Insert both end of strap into your glasses frame, appropriately move eyewear strap to find the right wearing position, the more forward, the better the fixing effect. made of neoprene, our sunglasses strap features good elasticity that provides wearers comfortable experience.