Ace Race Parts 24021 3.500 Flex Bellow (with Inner Liner) x 4.000 Overall Length - 304 StainlessAce Race Parts 24021 3. 500" Flex Bellow (with Inner Liner) x 4. 000" Overall Length 304 Stainless FEATURES 100% 304 Stainless Steel Construction 2 Ply Bellow Design Slip Fit Connection Type (must be welded) Directional Smooth Bore Inner Liner Extremely Durable in High Pressure Applications Pressure Tested (data listed below): 145 psi @ 68 DegreeF and 72. 5 psi @ 842 DegreeF Helium Leak Tested Prior to Shipment Ace Race Parts 304 Stainless Steel Flex