Construction Well spaced twin 1 7/8" wheels for exceptionally smooth running action. The wheels feature a hard, abrasion proof nylon surface which is particularly suitable for soft floor coverings such as carpets. Each caster is rated for 88 lbs (40 kg) load carrying capacity. The caster swivels freely 360 degrees for easy mobility. Installation Each caster is securely attached with 4 screws inserted through the steel mounting plate. Operation Each caster features a foot activated brake. In the raised position, the caster rolls freely. In the lowered position, the caster is firmly locked in position.