QUIET MOVEMENT:Carbon steel frame, 1.5 inch polyurethane(PU)wheel,360 degrees swivel caster wheels, double ball bearing wheels, easy to push, move easily,save energy, do not hurt the ground, no scratch the hard wood floor. Strong load capacity, each caster can carry 110Lbs, These casters are suitable for different occasions, commercial use, industrial use, home use, etc INCLUDES -Set of 4 swivel caster wheels with double brakes , 8 x screw nuts (4 x insert nuts and 4 x hexagon nuts with flange). Completely furnished and easy to install SIZE:They are swivel screw casters, universal 1.5 inches diameter stem casters with brake, set and nuts, threaded stem M8 x 25mm swivel casters,Mounting height 60 mm. Flexible rotation, safe and reliable, 360 degree rotation.Measure the thread type by Nut and Bolt Thread Gauge to avoid wrong buying LOCK MECHANISM:Caster wheels with double brake locks, it can brake the rotation direction of the bottom plate and the direction of the wheel forward, which is easy to operate, safe and reliable, because it is an iron brake, it is safer and more durable MULTITUDE USES: Replacement for office chair stem caster wheels, suitable for furniture, electric appliance, flight boxes, tool boxes, trolleys, etc 360 rotation, threaded stem, ball bearing, light duty, industrial brake design caster wheel. Used widely for the furniture, hand trolley, shopping cart, and kinds of industrial equipment.