Three Proofings Three Key Industrial Emergency Telephone is made of Fiber-Reinforced Plastic, it is a full-digital network radio/intercom. Dust cover can be added, it is a full-digital network radio and walkie-talkie, its core part adopts mature VOIP solution, stable and reliable performance; hands-free adopts digital full-duplex mode, the voice is loud and clear, and can Clear calls in the environment. Hands-free speaker output provides onboard 2.4W output or a 4Ω3W speaker can be connected through the built-in power amplifier board; broadcasting supports horn-type 8Ω5W speakers, and 30W/50W/80W/100W/200W can be customized for higher volume voice effects Wait for the configuration of the power amplifier board.