The Motorola RMN5042A remote speaker microphone features an emergency button and a 2.5mm ear jack. It is designed for Motorola devices and offers a proprietary connectivity option. This microphone is manufactured in the United States and is ideal for radio communication equipment, and other devices requiring a microphone. Please see for official Motorola compatibility list: https://www.motorolasolutions.com/en_xu/products/two-way-radio-accessories/audio-accessories/mobile-microphones/rmn5052.html
eBay