Two-way communication is accomplished through the use of speakers and microphones located on each side of the partition of this ticket window. The inside operator controls the operation by speaking into the gooseneck microphone. The SC-100L is 4″ in diameter with a gooseneck microphone, on/off switch, volume control for both “talk" mode and “listen" mode, and operates with a rechargeable battery pack. This ticket window unit is great for applications where a “natural voice" speak-thru is not enough to get the job done.