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