39 Pin Male Inline Connector.
This style comes in two sizes: W1 (which has 39 solder type contacts and is used for cables with 12 pairs or fewer), and W2 (which has 61 solder type contacts and is used on 16 and 20 pair cables). Each size has a male connector and a female connector. The male pins are fixed in a shell that has a locking ring attached. The female socket contacts are mounted in a receptacle shell that mates with and accepts the locking ring of the male connector.