The SHAPE Montreal Combo Black Wheels are made of steel components and are designed to fit 1” x 1” / 25.4mm x 25.4mm width stand legs, they are meant to be used in a clean environment with clear floors such as TV Studios. They included a soft braking system meaning you can gently push on the brake to slow down the unit until its desired position and then they can be locked in place by fully pushing on the brake. The wheels are made of non-marking material to protect floors and they come in a set of 3.