GI Sportz Oring C.U. 70A, 2-013 HP Piston Large Oring 1.79 GBP C.U. 70A, 2-013 HP Piston Large O-ring from GI Sportz The product is currently out of stock. Share Article Number: 614 Information Reviews C.U. 70A, 2-013 HP Piston Large Oring from GI Sportz.