Twin-Med Antistatic casters are a twin-wheel series that utilize a soft and quiet thermoplastic rubber tread. Combined with precision ball bearings in the wheels, these casters are easy to roll. Dual ball swivel raceway adds strength and increases swivel ease. Designed to protect the axle and bearings from debris, Twin-Med casters include a bottom undercover for the ultimate protection. With the same weight ratings of the Twin-Med casters, this version provides additional antistatic properties to help reduce the chance of electrostatic discharge.