... , 50, 57, 60, 63.5, 76, 89---- 1. carbon steel, stainless steel, pvc, nylon2. zinc-plating, galvanizing, chromeorplated3. Use press bearing or ... gravity roller could be made of nylon, weld pipe, stainless steel. For nylon gravity roller, the color could be grey ... . Gravity roller, light-duty rollers, snub roller, end roller, pulley roller, pvc roller, sprocket roller, retractable roller, taper roller, ...