The Shimano Flat Mount Adapter is the perfect solution for fitting flat-mount disc brake calipers onto a standard disc brake mount frame. With this adapter, you can easily upgrade your bike to flat-mount calipers and enjoy the benefits of this modern brake system. Versatile Compatibility: Designed for convenience and versatility, the Shimano Flat Mount Adapter is compatible with both 140 mm and 160 mm disc rotors. Whether you prefer the smaller 140 mm or the larger 160 mm size, this adapter can accommodate your preferred disc size. Simply flip the adapter to switch between the two options. Front Adapters with Mounting Hardware: Front adapters of the Shimano Flat Mount Adapter come with the necessary mounting hardware for hassle-free installation. However, please note that rear mounting bolts are frame thickness specific and need to be purchased separately to ensure a proper fit.