ABA original hose clamps - acid-proof A4 The acid-proof clamp is riveted at four points in the high-strength steel SS 2343/AISI 316. This clamp has one of the world's highest clamping forces due to the design of the thread and ABA's choice of production method. The clamp is a must where high clamping force and best corrosion protection is needed. For traceability, each clamp is stamped with the month and year of manufacture. Standard - S50 All parts in acid-proof steel 1.4436/AISI 316/SS2343. Min. time to red rust is 2000 hours. Comparable to W5.