SRAM Flat Mount Disc Brake Adaptor SRAM's Flat Mount Adaptor lets riders seamlessly switch between 160 and 140mm rotors. Simply flip the adaptor to the indicated side and secure your calipers to it. It's a simple but entirely practical little piece of metal that's capable of saving lots of riders from headaches. Features Alloy composition with stainless steel hardware In the box: 1 multi size (140mm and 160mm) adaptor, two stainless steel screws, two stainless steel washers | Sram | Flat Mount Disc Brake Adaptor | Black | Front-0F/20F, Front 140/front 160