The Rolls MX124 ProMix IV is a lightweight, compact, four-channel microphone mixer featuring 3-pin XLR inputs and transformer-balanced XLR stereo (L/R) outputs. Located on the side of the unit are four 18V DC phantom power switches and four low-cut filter switches. Individually switchable phantom power supplies allows the flexibility to use dynamic and condenser microphone simultaneously and low-cut filter switches eliminate hum, rumble and noise associated with wind and proximity effect. The front panel reveals level and pan controls for each channel. The 1/4" TRS phone and 1/8" (3.5mm) mini outputs can be used to feed headphones or as alternative stereo outputs. The mixer is completely portable, operating on two 9V alkaline batteries, making it a convenient utility in ENG/EFP, video, sound reinforcement and public address applications.