When you need some serious light, get the Blinder ARC 640. As one of the top range products from Knog, this light boasts a broad elliptical beam, big power, and beautiful looks. With 640 lumens of light, the ARC 640 will let you see and be seen no matter what road youre on. Powered by a USB rechargeable battery and comes in a 100% waterproof, integrated silicone package, you wont regret this purchase. Comes with two silicone removable straps for 25 – 30mm and 30 – 35mm diameter bars and even a helmet mount.