The LEMO S Series is one of the oldest series in the LEMO product line. LEMO continues to sell S Series connectors that are compatible with units sold in the late 1950’s. The contacts are Swiss screw machined brass/bronze with hard gold plating. The base insert configurations are multi-pin, coax and triax. (There are other more complex hybrid configurations; please contact LEMO for further information). There are 8 different sizes, ranging from 00 S Series (featuring about ¼” diameter shell) to 6S S Series (featuring about 2” diameter shell). The S Series is an IP50 indoor dust-tight rated connector. If an IP68 rating is desired, the LEMO E Series is a great alternative.