Brand New Aftermarket Automatic Voltage Regulator AVR The AVC63-4 voltage regulators are designed for use on 50/60Hz brushless generators. These potted regulators are economical, small in size, ruggedly constructed, and incorporate solid state technology with frequency compensation, automatic voltage build-up, overexcitation shutdown and EMI filtering as standard. Brand Name: DURAFORCE Part Number: AVC63-4, AVC634 Interchange Part Number: AVC63-4D, AVC634D Quantity: 1 Feature(s) Integrated circuitry for compact size, simplicity, high reliability. Extremely rugged. Exciter field current 4A continuous, 7A forcing. Regulation accuracy better than ± 1.0% no load to full load. Fast response. Frequency compensation. Overexcitation shutdown. EMI suppression. Parts can vary depending on the serial number of the machine.