The patented "C" insert pre-assembled MegaCrimp coupling gives world-class, leak-proof performance. It is designed with a patented "C" insert attached to the ferrule that accommodates hose of different constructions and wall thicknesses. The insert's design ensures crimping forces are evenly distributed to form a concentric seal. The "C" insert simplifies inventory requirements since one MegaCrimp coupling size can accommodate various hose outside diameters, on both one- and two-wire braid hydraulic hose. SAE J1453 Captive O-ring Groove for improved O-ring retention.