APC P4V surge protector Black 4 AC outlet(s) 120 V

Fail Safe Mode Most other surge suppressors continue to let power through even after their circuits have been damaged, leaving your equipment exposed to future surges. APC’s SurgeArrest fail safe, which means that once the circuit of an APC SurgeArrest has been compromised the unit disconnects equipment from the power supply ensuring that no damaging surges reach your equipment. Protection Working Indicator SurgeArrest will warn you if its circuitry has been damaged by heavy strike or power line surge and it is unable to provide 100% protection. If still under warranty, APC will then replace your damaged SurgeArrest free of charge. Transformer Block Spacing Connect bulky transformer block plugs without covering up other outlets. Noise Filtering Surge Protector attenuates EMI/RFI line noise that can cause data errors and keyboard lockups, ensuring better performance of protected equipment. Building Wiring Fault Indicator This LED informs users of potentially dangerous wiring problems in the wall circuit. IEEE let-through rating and UL 1449 compliance The 'Institute of Electrical and Electronics Engineers' (IEEE) Let-Through Voltage rating is based on a test that subjects a Surge Protector to a 6,000 volt spike. The rating equates to the amount of excess voltage that reaches connected equipment. The lower the number, the better the performance of the Surge Protector is. Underwriter's Laboratory's UL1449 surge protection safety standard uses these ratings to help users gauge performance. UL's best Transient Voltage Surge Suppressor (TVSS) Let-Through Voltage rating is "300V".