Features： 3-inch diameter twin wheel with soft roll rubber wheel surface, no marking on carpets or any kind of natural and engineered wood floor, tile floor, Laminate, Tile, Slate, and all other Hard Floors Stem Length: 7/8". Stem Diameter: 7/16" -- universally fit all office chair bases with 7/16" (industry standard) mounting holes 110-lb load capacity per caster, total 550lbs loading capacity Specifications： Type: Office Chair Caster (No marking, No noise) Color: Black+Clear Material: Polyurethane layer & Nylon body Wheel Diameter: 3 inch (75mm) Installing height: 4-1/4inch (108mm) Stem Diameter: 7/16 inch (11mm) .
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