70-90mm Constant Tension Worm-Drive W3 - 03017885 Main difference between the W3 constant tension worm-drive & the standard Mikalor worm-drive is to be found in the inner-ring insert incorporating a spring. This spring-loaded insert maintains constant pressure around the hose in case of sudden variations in temperature &/or vibration thereby avoiding leaks. Screw: AISI 430 stainless steel. The fact that this clamp guarantees leak-proof hose assemblies with both gaseous fluid & liquids makes it ideal for applications in car, tractor or heavy machinery engines. Moreover, the non-perforated cold formed band together with the rounded band edges make sure that no damage occurs to the hose. This clip complies fully with the DIN 3017 norm & also with the RoHs directive EU/2002/95/EC dated 1st July 2006. Band and Housing: X6Cr-17 Stainless steel (DIN 1.4016) AISI 430 The maximum application pressure can vary depending on the type of hose used and the geometry of the coupling. Spring-loaded insert: AISI 301 Stainless steel *The bandwidth does not take into account the spring-loaded insert. The maximum application pressure can vary depending on the type of hose used and the geometry of the coupling. Worldwide patent.