AV-JEFE AVL623 Black Color Professional Mini Sweat Resistant Headset Microphone for AKG Wireless Systems Clear voice pick-up. Designed for speech, preach, lecture, broadcasting, conference. (This mic is NOT designed for use in Fitness Classes or Training Classes.) Super lightweight, thin, flexible & durable frame. Easy wear-on style for comfortable, long-hour use. Flexible and slim gooseneck boom for close talk and easy mic positioning. Compatible with AKG transmitters: PT40, PT45, PT60, PT61, PT80, PT81, PT400, PT450, PT2000, PT4000. Boom Length: 4.5 inches, sitting by user's cheek. (including 1.5 inch gooseneck tip for easily adjusting mic capsule directions)