Soundstream RUB1.700 1x400 Mono Block Amplifier (Blue) Midnight Blue Finish w/ Brushed Accents Regulated MOSFET Pulse Width Modulated Power Supply Three-Way Protection Circuitry (thermal short impedance) Twin Stack Technology TM (strap amps together for double power) Delayed On/Off Circuit Variable Low Pass Crossover Variable Bass Boost Variable Subsonic Filter 180 o Phase Control Pre-Amp Output Dash Mounted Remote Gain Control Direct Wire 4 ga. Power 8 ga. Speaker Terminals Direct Wire 0 ga. Power 4 ga. Speaker Terminals (2500D)