AV-JEFE AVL623 Beige Professional Mini Sweat Resistant Headset Microphone for Shure Wireless Systems. New Ergonomic, Lightweight, Flexible Frame Great Quality Professional Headset Mic !!! Clear Voice Pick-Up. Great for Speech & Lecture. (NOT designed for use in Fitness Classes or Physical Training Classes.) Compatible with Shure models: L1, L11, LX1, SC1, SLX1, U1, UC1, UT1, T1, ULX1, UR1, PGX (NOT compatible with Telex transmitters) ** Important: For wireless receivers & transmitters of other brands, even the connectors look identical, they might not be compatible. (ex: NOT compatible with Telex transmitters). ** Ergonomic & Lightweight. PVC Coated Flexible Frame, Easily Adjust to Fit. Unique Slim Gooseneck Boom Design for Easy Mic Positioning. Boom Length: 4.5 inches (Sit by user's cheek).