Description: The antenna gain signal line receives the host signal. The hole is smooth and the body is made of metal. JW306B interface,3 sections stretchable. Stable signal and long service life. Suit for wireless microphone. Size Chart: Contraction Length: Approx.187mm/7.36inch Stretch Length: Approx.420mm/16.54inch Hole Diameter: Approx.4mm/0.16inch Package Includes: 1 Piece Microphone Antenna