HBM-04BT 4-Channel Multiplexer, B/W, Duplex, Digital Video HCM-04BT Triplex/HBM-04BT Duplex Super high resolution picture with 720*480(NTSC),720*576(PAL) On-screen programming menu On-screen adjustment its brightness/contrast/color/hue of each channel Sequential switching mode provided 4 looping camera outputs for usage of other accessories 3 recording mode provided