Rear of the LCD display 11. AC IN connector This connector connects the power cord. 12. Cable holder This parts secures cables and cords to the monitor. 13. Security lock hole The security lock hole should be used with the Kensington Micro Saver Security System. Micro Saver Security System is a trademark of Kensington. 14. Audio input jack for INPUT1 This jack inputs audio signals when connected to the audio output jack of a computer or other audio equipment connected to INPUT1 15. HD15 input connector(analog RGB) for INPUT1 This connector inputs analog RGB video signals(0.700 Vp-p, positive) and sync signals. 16. Audio inputjack for INPUT2 This jack inputs audio signals when connected to the audio output jack of a computer or other audio equipment connected to INPUT2. 17. HD15 input connector(analog RGB) for INPUT2 This connector inputs analog RGB video signals(0.700 Vp-p, positive) and sync signals. 18. Audio input jack for INPUT3 This jack inputs audio signals when connected to the audio output jack of a computer or other audio equipment connected to INPUT3. 19. DVI-D input connector(digital RGB) for INPUT3 This connector inputs digital RGB video signals that comply with DVI Rev.1.0. 20. Audio output jack This jack outputs audio signals to speakers or other audio equipment.