... :15-40KG 3.PU,different fittings available 4.Good quality,reasonable price. 1.Product specifications:1.Caster materials:Plastic2.Loading ... capacity: 15 to 40kg per caster3.Wheel diameters: 30, 40,50mm4.Matching ... is from 15mm to 300mm, materials include rubber, TPR, PU, plastic, nylon, cast iron, pneumatic, phenolic and sandwich, etc. ...