PMMN4127A PMMN4127 - Motorola WM500 Wireless Remote Speaker Microphone POC -- The WM500 is our thinnest wireless remote speaker microphone and is built with an internal battery that lasts up to 40 hours. The WM500 is compatible with PTT-over-Cellular (PoC) applications such as WAVE PTX™. IP67 rated. Kit includes USB-A to USB-C Cable for charging.