Double wheel straight threaded stem connector casters.This twin-wheel chair caster can be equipped in chair, quite great replacement! features double wheel with 2Inch in diameter, design with threaded stem connector.Threaded stem connector caster made from plastic wheel with metal holder to prevent corrosion. It is widely used on everything from office chairs to portable equipment, small machinery, trolleys and rack, etc.The 2 inch wheel chair caster can be used on low-pile carpeting, chair mats and all hard floor surfaces.Wheels with a dual escalator raceway system balances the load evenly for smooth swiveling and effortless rolling.Economical, long lasting black threaded stem caster can be used on most office chairs as a portable equipment.