This VGA over Cat 5 extender/repeater is specially designed for use with StarTech.coms ST121 VGA Video over Cat 5 extender series, which is typically comprised of a transmitter unit (ST1214T or ST1218T) and a Receiver unit (ST121R). The VGA extender repeater adds to the extension distance capability, for a total of 300m (984 ft.) between the transmitter unit and receiver unit. For even more versatility, up to three repeater units can be used between the transmitter and receiver units, allowing monitors to be connected between the two units.