... ,window roller. standard or nonstardard bearing. POM,nylon covered. Long life. Pulley:1,Standard bearing: 608,608z,608zz,625,625z,625zz,693,693z ... ,693zz.2,Bearing steel material: carbon steel or bearing steel.3,We accept make the nonstandard bearing ... material: 1, Nylon. 2,POM.4,Packing: Pallet.Drawing: Plastic bearing