Deliver the power your amp deserves Crutchfields 1/0-gauge amplifier wiring kit contains the wire and hardware necessary to supply power to your amplifier safely, efficiently, and economically. This wiring kit does not include RCA patch cables or speaker wire . You may need to purchase those items separately, in order to complete your installation. Please note that the 1/0- gauge power and ground wires in this kit are very thick, up to 3/8 inches in diameter. Make sure your amplifiers power and ground terminals can accept wires of this size before ordering. Power ratings and amp efficiency Most amplifiers come in two distinct "Classes" of technology with different efficiencies and power wire size requirements. Class AB amps typically feature 50% to 60% efficiency, while Class D amps are usually 75% to 80% efficient. This Crutchfield wiring kit was designed to accommodate the energy demands of a Class AB amplifier with a total output of up to about 2,100 watts RMS, or a Class D amp with up to 3,300 watts RMS output. Crutchfield wire Crutchfield wire is made of oxygen-free copper, with no impurities that could raise its resistance to a signals flow or add interference. Crutchfield wire meets all Consumer Technology Association (CTA-2015) standards for size, resistance, and insulation quality.