SHIMANO 160MM IS DISC BRAKE ADAPTERIMPROVISE. ADAPT. OVERCOME. Disc brakes are a wonderful thing for all types of bikes. The only problem is the brakes you own might not fight on your frame. If this ever happens, you can easily use a disc brake adapter. The Shimano 160mm IS Disc Brake Adapter is designed for 51mm International Standard (IS) frames and 74mm Post Mount (PM) calipers. Features Designed for 51mm IS frames and 74mm PM calipers Works with 160mm rotors Includes mounting hardware | Shimano | Shimano | 160Mm Is Disc Brake Adaptor Rear Post Mount Adaptor 160Mm