The 888 I/O is an audio interface used with Pro Tools Project (3.2 or later), Pro Tools III (3.0 or later), or Session 8 PC (2.5 or later). It connects to any of the following cards: PT Project, Disk I/O, Bridge I/O, or Session 8 PC I/O.Analog Input/Output: Balanced XLR, pin 2 hot, internally switchable +4dBu/-10dBu per channel.Output Impedance: 50ohms typical (45 min, 55 max)Input/output Level Trim: 6-turn cermet trims.Digital I/O: 4 AES/EBU pairs (XLR); 1 S/PDIF pair (RCA); 16-bit I/O on NuBus/PC, up to 24-bit I/O on PCI (software dependant).External Sync: 256x sample rate (Super Clock) in/out, about 3 Vpp, BNC connectors.NuBus Card Connector: 50-pin, SCSI2-type female.Sample Rates: 44.1k or 48k.Analog-to-Digital Converters: 1-bit Delta-Sigma;128x Oversampling; 16-bit (18-bit with PCI).Digital-to-Analog Converters: 18-bit; 64x Oversampling.Operating Level: +4 dBu nominal (factory calibrated to 18dB headroom).Maximum Input Level: +26dBu.Frequency Response: 20Hz to 20kHz, +/-1dB.Signal-to-Noise Ratio: -104dB (A-Weighted).THD + N: .004%, 0 dbFS @ 1kHz, 22 Hz - 22 kHz bandwidth.Power Requirements: 90-260 VAC, 47-63 Hz, 30 watts, auto-switching.Dimensions: 2U External rack mount device; 19" x 3.5" x 9.75".Weight: 7 lbs.