Bassknob not included The product is Used Used means: the product was used and still in good working condition.It may have some scratches after previous installation and signs of wear.The product is working, tested by our technician and still under the limited warranty for a 3 month. Warranty doesn’t cover: Damage due to misuse of product Damage due to using the product outside of the recommended specifications. Damage due to negligence or abuse Improper installation (including professional installation) Damage due to clipping, overpowering and/or distortion (improper tuning) Specifications Model AAB-2000.1D Atom Class D Number of the channels 1 Frequency response 15-20000 Hz 1 Ohm RMS Power (14.4 V) 1960 W 1 Ohm RMS Power (12 V) 1800 W 2 Ohm RMS Power (14.4 V) 1300 W 4 Ohm RMS Power (14.4 V) 750 W Minimum permissible load on the channel 1 Ohm Input SPL 0.2 - 6 V Low pass filter 80-20000 Hz High pass filter 15-1000 Hz Crossover 12 dB/Oct Bass frequency adjustment 35-70 Hz Input terminal 4 Ga Output terminal 8 Ga Damping factor ≥ 210 Working voltage 9 - 15 V Signal-to-noise ratio ≥ 100 dB Size (W×L×H) 6.30 × 6.89 × 2.50 inch Gross weight 4.85 lb (2.20 kg)