The testo 755-2 includes important additional features: phase rotation, voltage range up to 1000V, and the unique feature which allows the user to check for voltage using only a single lead. The testo 755 current/voltage testers are fast and easy to use, especially when you are testing many circuits. The convenient open-jaw current tester automatically turns on when voltage exceeds 6V. It then auto-selects the correct parameters and range for your test. These rugged testers are suitable for virtually all your daily electrical measuring tasks.