The CAT5 to Serial Remote Hub allows you to control 4X4 Matrix switchers from 4 separate locations. The CAT5 to Serial Remote Hub connects to the matrix switch via RS-232 cable. CAT5 cables extend up to 4 4X4 Matrix RMTs each up to 1000 Feet. Each 4X4 Matrix remote controls one of the outputs from the 4x4 Matrix Switcher. The CAT5 to Serial Remote Hub gives you more control from more locations.