Countryman E6OW-S3 is a Omnidirectional Earset Microphone with Lemo 3-Pin Connector for use with Transmitter Models: Sennheiser SK-50, SK250, SK3063, SK5012; Shure All with Lemo 3-Pin and Zaxcom TRX900, TRX900AA. Very high quality audio, good rejection of feedback and unwanted sounds. Extremely light and stable on the head. Once shaped to fit your head, the tough springy boom keeps its shape when stored.