apc essential surgearrest 7 outlet phone line protection
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 . status indicator led s provides a quick visual indication of your unit s status . transformer block spacing connect bulky transformer block plugs without covering up other outlets .