The diameter of a hose connection can change with time and temperature. As an engine heats up or cools, for example, the diameter of metal exhaust ports can expand and contract. Additionally, virtually all rubber hoses compress (cold flow) after being clamped. This can result in a torque loss that can exceed 80% of the installation torque. Constant Torque Clamps can actually change their diameter while maintaining their clamping torque, thus compensating for changes in hose and fitting diameters. Ideal for engine hoses -automatically adjusts for heat and cold Unique worm gear Belleville spring washer assembly (401 stainless steel) Band: 5/8" wide 304 stainless steel 3-year warranty