plastic roller manufacturer plastic free roller (steel pipe with zinc plate) sell plastic rollers with and without cores, sizes 25x1.5, 38x1.5, 50x1.5, 60x1.5, 60x2.0, 60x3.0, 76x3.0, 89x3.0 selling roller heavy duty, steel roller sizes 38x4.0, 50x3.5, 60x4.5, 76x4.5, weight capacity/each