Specifications: Made of metal material, it is durable, non-slip, and the hardness of the screw is improved, which can ensure long-term use. By using a semi-metal thick plate, it helps to maintain low speed when riding, improve the stability of use, and enable your bicycle to be controlled smoothly. It can be easily installed without disassembling the caliper, which is suitable for most standard mountain bikes, road bikes, folding bikes, but please note that it is not suitable for ordinary bicycles. The front disc brake marked F160/R140 is suitable for installing front wheel 160# disc and rear wheel 140# disc, generally more front wheels are installed. The rear disc brake marked F180/R160 is fit for the front wheel 180# disc and the rear wheel 160# disc, usually more rear wheels are installed. Item Name: Mountain Bike Disc Brake Material: Metal Features: Wear-Resistant, Stable, Easy to Install, Durable, Size: 12cm x 8cm x 4cm/4.72" x 3.15" x 1.57" (Approx.) Hole Distance: 51mm/2.01" (Approx.) Notes: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Package Includes: 1 x Front Disc Brake Or 1 x Rear Disc Brake