These Simson Replacement Cartridge V-brake are suitable for V-brake Cartridge Brake Shoes. Because the brake pads of these brake shoes can be replaced, it is not necessary to replace the entire brake shoes. Remove the locking pin on the top of the brake shoe with a pliers. Slide the worn cartridge against the travel direction out of the brake shoe. Slide the new brake pads into the brake shoe and secure with the locking pin. The Simson Replacement Cartridges have a length of 72mm and are supplied per two pieces with fastening pins.