BS Neptune™ Chain is a Tsubaki BS chain that has undergone a special surface treatment. The link plates, bushes and bearing pins have a special two stage layer applied in order to provide the maximum protection from the operating or environmental conditions. (Spring clips are SUS301). Neptune™ Rollers have a special coating designed to resist the corrosive conditions as well as the severe dynamic contact between roller and sprocket. This chain is suitable for use in applications that are subject to akaline cleaning and environments exposed to seawater, acid-rain and other adverse weather conditions. This chain does not contain any chemically hazardous substances such as Hexavalent Chromium, Lead, Cadmium and Mercury as regulated by RoHS.