Window Speaker Intercom System for Bank Ticket Office Restaurant Hospital You can use the conversation between the inside and outside of the window for the customers' evaluation of the salespersons, and for the supervisor's evaluation of each window. 1.Usage: the bank staff use the master station to talk with guests, and the guest use the substation can talk with bank staff as well. 2.Installation: the master station is installed in the working place and the sub station out of the working room. 3.Application: bank, stock office, hospital, post office, Box office, Toll station, etc. Functions and Features: 1)Hands-free two-way talkback with full automaticity, microphone is clear for both side; 2)Microcomputer controlled circuit with squelch function, can solve echo and squeal problems; 3)Adopts high-powered mic, the voice is lifelike and clear; 4)Easy installation, there is only one wire for master station and substation connection. 5)Volume of master station and substation can be adjusted separately. 6)With recorder jack, can output both route's sound and signal. 7)Have individual button to turn ON/OFF MUTE function for both of side When you turn on Outside "mute" key, outside guest can’t hear inside voice. Also when you turn on Inside "mute" key, inside worker can’t hear outside voice. Specification: Working voltage: DC12V/0.5A Input voltage: AC 110-240V Work power: 2W, 100Hz-15Khz Inside microphone: -48db 20Hz-20Khz Outside microphone: -48db 20Hz-16Khz Cable length: 3M Main base Dimension: 162*110*40mm Substation dimension: 80*20mm Material: plastic Specification: Working voltage: DC12V/0.5A Input voltage: AC 110-240V Work power: 2W, 100Hz-15Khz Inside microphone: -48db 20Hz-20Khz Outside microphone: -48db 20Hz-16Khz Cable length: 3M Main base Dimension: 162*110*40mm Substation dimension: 80*20mm Material: plastic Packaging List: 1 x Dual-way counter interphone 1 x External speaker 1 x Charger 4 x Adhesive 1 x English User Manual Packaging List: 1 x Dual-way counter interphone 1 x External speaker 1 x Charger 4 x Adhesive 1 x English User Manual