Tester works with the following NEMA Types; 1-15, 5-15, 5-20, so one needs to carry just one toolReceptacle contacts are monitored independently for complete assurance of compliance and trouble-free power system operationThe completely insulated housing allows testing to be performed on live circuits to allow continued, uninterrupted power serviceImpact resistant housing and carrying case provide tester protection and an exceptional service lifeImpact resistant plastic tester housingStainless steel tension tester plug bladesIndustrial duty gradeNylon materialCarton packaging