This 4 Port transmitter unit is specifically designed for use with StarTech. com's ST121 VGA Video over Cat 5 extension series. Comprised of a 4 port VGA extender unit (this device - ST1214TGB) or an 8 port VGA extender unit (ST1218TGB) and one ST121RGB Receiver Unit per display as necessary, the VGA and Audio extension series can transmit a single VGA output and corresponding audio to four or eight displays/receivers over standard Cat 5 UTP cable.
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