This is a roller skates exercise Brake Stopper. This brake stopper is easy to use and convenient to install on most kinds of roller skates. It can be a great tool for those roller skates enthusiasts, and they will like it. Roller Skate Brake Stopper is made of practical material, safe to use and durable for time of use. Features -Color:Black -Material:Rubber -Size: 10.50X8.80X4.00cm/4.13X3.46X1.57in -Note: There is an error in manual measurement, the size error does not 1cm -Provides stability for fast stopping. Easy to install and use for your convenience. -Anti-slip sole prevents skidding, Inline Skate Brake is great for balancing your roller skates -The roller skate brake can improve the braking performance and reduce the braking noises -Roller Skate Stopper is made of sturdy material, safe to use and durable for time of use. -This professional brake block is sturdy, and non-slip and can be a good tool Package list: 2 Skate Brake Pad 2 x Short Screws 1 x Long Screw