1975-1982 Corvette: 396-502 Tube Size 2.125" x 45", Collector Size 4", Collector Length 10", Port Shape: Round;Tuned-length primary tubes for maximum exhaust scavenging and velocity; All necessary hardware included for a complete installation; Slip fit side tubes for leak-free seal; Designed for optimal performance; Industry’s best welds for durability; 5/16” machined flanges for a perfect seal; Long transition collector for decreased back pressure; Light weight & sturdy 18 gauge tubing; Mandrel-bent tubing for smooth exhaust flow; Replacement Hooker mufflers available in straight-through or reverse-flow versions; Requires use of motor mounts that locate the engine in the factory location;