cylindrical roller bearing: 1.Density 2.Precision 3.Heat Cold-rolling process roller bearingOur main products including: Low-noise deep groove ball bearing(more ... than 6000 series)Spherical roller (21000,22000,23000 series)Tapered roller (3000 series and inch ... ball 1200,1300,2200,2300 series.Spherical plain bearing ( GE,GEG)Cylindrical roller(NU,NJ,NUP)