Description Manuals Videos Articles Clemco 21561 - O-ring, .864 ID x 1.004 OD Apollo 60 HP Item # 21 Customers Also Viewed Piston, u-seal, S/King #100018 $61.39 Piston, diaphragm, S/King #100014 $62.36 Clemco Apollo 600 Cape, Silver-Grey with Red … #23818 $105.24