Twin Wheel Casters With well-spaced wheels, these twin-wheel casters offer exceptionally smooth running action. Incorporating a hard, abrasion-proof surface finish, they are particularly suitable for soft floor coverings such as carpets. Mounting This wheel is designed to be mounted via the attached mounting plate with four screws. Construction This product has a Nylon wheel & hood, steel support shaft, and steel mounting plate. How Sold This item is sold as a set of 4. Selecting a quantity of 1 will result in 1 set of 4 casters being ordered. Specifying a quantity of 2 will result in 2 sets of 4 casters in each set or 8 casters being ordered.