The Everwell electronic voltage surge protectors for refrigerators, freezers, computers, printers, TV’s, etc of up to 27 cubic feet. Professionally designed to protect against volt./current surges beyond rated value. These units quickly cut power during blackouts, High and Low voltage. Voltage protectors feature: 3 minute delay time connection, bright LED lighting specifying (Normal, High, Low voltage and Time Delay), easy installation, single output, and cutoffs of under-voltage at 90 V / over voltage at 130 V. Other specs include: Nominal Voltage: 110-115V AC, 50/60Hz / Max Charge Capacity: 20 Amp. / Surge protect: 140 Joules / Connection Wait Time: 30secs / Operating Conditions: 23 °C to 131 °C.