Surge Suppressor, Low Voltage AC SPDNominal Discharge Current 20kA, Voltage 277/480, Phase 3Y, Wire 4, Number of Poles 3, Max. Surge Current Per Phase 50kAMax. Continuing Operating Voltage 320, Voltage Protection Rating 1200V(L-N), 2000V(L-L)Modes of Protection 7, Mounting Style Surface/Din Rail/Chase Nipple, Material of Construction Polycarbonate, Enclosure Type NEMA 4XWire Gauge 10AWGLength 9, Width 9, Depth 5, Standards UL 1449 3rd Edition, Type 1 SPD Siemens Surge SuppressorsHard-wired Type 1 SPDs, formally known as TVSS, are ideal surge protection solutions for commercial/industrial, OEM, and residential applications. Most models carry a 20kA I-nominal rating, which is required for UL 96A lighting protection certification. Features include indoor/outdoor enclosure ratings, thermally protected metal oxide varistor technology, and LED protection status indication. 100kA, 200kA, and 300kA models include EMI/RFI filtering and are UL 1283 Listed.UL 1449 3rd. Edition