Protecting Rating: 327 Joules. A higher joule rating means a higher protection level. Specifications: UL 1449 Suppressed Voltage Rating (L-N, N-G, L-G) - 330V; Joule Rating - 327; Line Voltage - 125VAC; Maximum Line Currant - 15 AMP/1875 Watts; Maximum Surge Voltage - 6kV; Maximum Surge Current - 19.5kA; Typical Response Time - 25nsec; EMI/RFI Attenuation (up to) - 40 dB; 3-Wire Grounding Outlets - 3. For limited lifetime warranty, connected equipment warranty, specifications chart and instructions, see insert inside. UL Listed. Limited Lifetime Warranty.