20 mm Extreme Low Bleed 20 mm PTFE/Natural Crimp Septa Skived 1000 N9302976 PTFE 0.005”/ Natural Silicone 0.125” 20 mm Ultra Low Bleed HS Cap Non Pressure Relief Skived PTFE 1000 N9302977 0.005”/White Silicone 0.125” 20 mm Ultra Low Bleed HS Cap 20 mm Crimp Pressure Relief HS 1000 N9302975 Cap Skived PTFE 0.005”/Silicone 0.125”