Security door silent roller,Austalia market,plastic housing,steel bearing,nylon wheel, over 100 lbs window,1.25 inch diameter wheel,single wheel, 10 years gurantee,existing mold,for security sliding door&window,high-quality,10000 cycle testing,20years experience OEM ,manufacture factory,45days delivery,also can produce as your print or sample,30days to make mold and samples.