1. POTS -3dB,cut off frequency: 7,8kHz, 2. POTS pass ripple loss: (20Hz to 4kHz)+/-0.5dB 3. Attenuation: 30-300kHz>-65dB, 30-1104kHz>-55dB 4. DC Resistance each line: 12.5 Ohms,Max. 5. Insertion loss (200Hz to 4kHz): -0.5dB Max. 6. Return loss: 300-500Hz>-16dB, 500-2000Hz>-18dB, 2000-2400Hz>-18dB 7. Longitudinal balance(CMRR):200Hz-1kHz): -58dB Min. 3kHz: -53dB Min. 8. POTS loop current: 100mA DC 9. Envelope delay distortion (0.2 to 4.0kHz): 100usec. Max. 10.Impedance (300Hz to 3.4kHz): 600 Ohms 11.Hi-Pot test: Tip to Ring, DC 250V/1mA 2 Sec. colours: white or black