1Anti-interference and noise-free function. 2Two-way voice intercom communications technology, automatic identification of processing speech signals during a call does not require any action. 3Dedicated anti-side tone processing chip, with auto-mute function. 4Application of completely automated call control, outside the machine's microphone and speakers to use the integration of design and front-line system of the host to connect, easy installation. 5Inside and outside the two-way voice signal output(recording by the bank teller), a stereo jack output mode can prevent voice recording function controlled by the power switch and the function buttons. Features: Anti-interference and noise-free function. Two-way voice intercom communications technology, automatic identification of processing speech signals during a call does not require any action. Dedicated anti-side tone processing chip, with auto-mute function. Application of completely automated call control, outside the machine's microphone and speakers to use the integration of design and front-line system of the host to connect, easy installation. Inside and outside the two-way voice signal output(recording by the bank teller), a stereo jack output mode can prevent voice recording function controlled by the power switch and the function buttons. Application: bank, securities, hospital, bus station Where guard glass again theft is installed. Specifications: Condition:100% Brand New Color: As shown in the picture Plug:110-240V US,110-240V EU(Optional) Working voltage: DC12V Maximum operating current: 1A Main sound (sub sound): 3W Inside microphone: -42db Outside microphone: -42db Package List: 1 xDual-way Counter Walkie Talkie 1 xExternal Speaker 1 x12V Power Supply 2 xAdhesive 1 xInstruction Manual