large remote speaker microphone is easy to operate even while wearing gloves large remote speaker microphone is easy to operate even while wearing gloves The noise-canceling acoustics negate background noise so your voice come through loud and clear when you speak directly into the microphone. A programmable orange emergency button and audio jack to attach earpieces allowing for discreet communications. Compatible, APX 4000, APX 6000, APX 6000XE, APX 7000, APX 7000XE, MTP830 S, MTP850 S, SRX 2200