MTP40S-UN is a compact bodypack transmitter designed for professional wireless mic use. It introduces Ultrasonic Narrowband (UN) operation with a dedicated 70 dB ultrasonic filter, plus a switchable wideband mode for legacy Wisycom systems. It offers up to 232 MHz switching bandwidth, 200 kHz tuning steps, and ENR/ENC processing for clean audio. Powered by 2 AA cells, it supports LEMO or DPA Microdot inputs and +26 dBu max input, IR setup, and low power consumption for long wear.