1. Tightness good 2. Rubbing 3. Environmental protection material 4. Anti-corrosion PTFE extruded ... )CallAllowed tolerancecallAllowed toleranceSFBN–14,5,60.481000 50 7,8,90.58 0 10,13,15,161.11000 3.60 SFBN ... .6 0 55,60,65,702100-300 75,80,85,90 2.51000 110,120,1302.5 140,1500 180,200,2503100 ...