1.44"- 1.58" (37MM-40.5mm) Stainless Steel Exhaust Clamp W/Hex Key Socket Bolt, Stainless Steel Exhaust Clamps Are The Best Way To Keep Your Exhaust System Looking New. Chrome Clamps Just Do Not Stand Up To The Repeated Heating And Cooling Cycles Of The Exhaust System And Begin To Rust. Helix Racing Products Has A Complete Line Of Stainless Steel Exhaust Clamps For Almost Any Application. This Barrel And Band Design Provide For Superior Clamping Pressure And Have A Low Profile Hex Key Head Adjusting Bolt. Look At These Clamps And You Can See They Are A Step Above. Available In 10 Sizes.