The ST-850 is a very flexible in function Gooseneck microphone . Not only is it a wired Back Electret Condenser super cardiod 312mm Gooseneck Microphone that requires phantom power. It is also compatible with 4 pin mini XLR JTS wireless belt packs for example UF-20TB, R-4TB, RU-G3TB, IN264TB, PT-900B, PT-850B, PT-920B (G), PT-950B and PT-990B. It utilises the belt-packs own phantom power so you can go wireless ! Slot underneath the base to hide the belt-pack.