Pop In Style Amp Casters with Sockets - 2" Non-Marking Polyurethane Wheel for Amplifiers Set of 4 Pop In Caster with Polyurethane Wheel - Made in USA Durable - Floor Safe - Non-marking and non-marring 2" wheel - 90 pound capacity per caster High quality replacement for soft rubber casters Round plate for 7/16" grip ring stem