Characteristics: High high quality workplace chair rubber swivel caster Strong and safe for all office chair bases with mounting holes Dual wheel design improves weight distribution and tender operation, smooth to slip and turn Turns and rolls freely and quietly in all instructions without maintenance Smooth rubber wheel surface ensures no marks left on carpets or any sort of engineered pure wooden flooring, tile flooring, particular floors and Concrete / Smooth asphalt flooring Easy adjustment-just click on Specifications: Material: steel and rubber Wheel diameter: 73mm (2-7 / 8 ") -about 3" Shank length: about 22mm (7/8 inch) Shank diameter: about 10-11mm (7/16 inch) (see the picture) Color: black with transparent Package includes: 5 x wheelchair 尺寸 轮径(mm) 轮宽(mm) 承重(kg) 安装高度(mm) 插杆尺寸(mm) 2.5寸 sixty three 24 40kg eighty two 11*22 3寸 seventy five 24 50kg 95 10*22/11*22