Klein Tools Digital Clamp Meter AC Auto-Ranging 400 Amp with Temperatures The Klein Tools CL220 400A Digital Clamp Meter easily measures AC current and AC voltage through the no-contact clamp and DC voltage with the included test leads. Equipped with TRMS (True Root Mean Squared technology), the CL220 can accurately read alternating currents or dirty power for reliable measurements no matter where you are. The included test leads measure continuity while its thermocouple tests for temperature. This all-in-one tool can reduce on-site work time by integrating these electronics in one device and putting it in one small package. The Klein Digital 400A Clamp Meter has an ergonomic body design for one-handed use as well as an optional magnetic hanger for hands-free operation if needed. All units are clearly marked as well as having a backlit LCD screen for easy reading even in a low-lit area. This meter has a battery indicator and has included required batteries so it can be used right out of the box.