REPLACE THE CRAPPY PLASTIC WHEELS:Our Stem Casters are well built and sturdy roll smoother,have a softer wheel for hardwood. SIZE OF CASTER WITH BRAKE:The stem locking casters size is 5/16"-18x1"(NOT METRIC M8),thread diameter is 5/16" and the stem length is 0.79"(20mm).PLEASE NOTED THIS IS NOT METRIC M8 SIZE. MULTI NUTS CHOCIE:1:Hex Nut(Tighten) 2:Flange Nut(Tighten) 3:Nylon Nut(Tighten) 4:Set Screw(Easy Screw),you could choose what nut you want. VARIOUS APPLICATION:The stem casters could be used for a tennis racquet stringing machine,the base of some metal shelving,heavy cutoff saw,metal shelf unit.vise stand, mobile hospital bed tray and more. HEAVY DUTY SWIVEL STEM CASTOR:Made of Polyurethane and Steel,roll quiet and no scratch on floor,set of 4 stem casterscould load up to 400lbs. WHAT SIZE IS 8T8 STEM CASTER WHEELS： The stem caster wheels size is 5/16"-18x1"(NOT METRIC M8) Threaded SIZE,stem diameter is 5/16",stem length is 0.79"(20mm),the wheel diameter is 2"(50mm),

NO SCRTACH ON YOUR FLOOR： Heavy Duty Swivel Stem Casters made of PU Foam polyester dual locking with 19 steel balls,cart furniture will enjoy quiet rolling and smooth on rolling on any of floors,no scratch on floors.Each set loads up to 400 lbs.

WIDE APPLICATION： 3/8" screw stem casters could be used for antique handmade table saw,heavy pedestal fan,industrial sewing machine table,heavy-duty rolling base for a potted plant, welding cart,a tool table for a CNC and more.

SPECIAL LOCKING FEATURE： The stem brake caster wheels featured dual locking,it could be locked when you don’t want your furniture move,stay in place like a quiet stone.Various Nuts choice meet different requirement.