... Hydraulic seals usually need to be higher friction seals than pneumatic seals but often operate under lower operating speeds.3) ... can include internal (rod seal), external (piston seal), symmetrical or axial seal. With the internal (rod) seal, the seal is fit into a housing ... , ROI, SPNRI, WR, BRT, RYT, DB, TAY, VB, TC Pneumatic Cylinder appropriative seal:PGY, PNY, GLY, PSD, PDU, PPY, PRY Automotive ...