... specifications:1.Caster materials:Plastic2.Loading capacity: 15 to 40kg per caster3.Wheel diameters: 30, 40,50mm4.Matching with various fittings ... corrosion-resistance. Now it already has become a professional caster company which integrates design, manufacture, assemble, inspection and ... 2011 is USD27,000,000. Our wheel diameter is from 15mm to 300mm, materials include rubber, TPR, PU, plastic, nylon ...