The T+PRO and T+ electrical testers offer all the functionality that electricians look for in volt meters and voltage and continuity testers. Both have three ways to detect ac/dc voltage: light, sound, and vibration. Both offer the added functionality of a GFCI trip and continuity beeper, plus the convenience of a built-in flashlight. The T+PRO Electrical Tester comes with a rotary field indicator for troubleshooting three-phase systems, resistance measurement to 9.99 KOhms, as well as a backlit LCD display for easier viewing.