I bought 2 of these gauges I was so happy to finally get one it's like a novelty now everyone wants one and can't get enough of it them here anyway After 2 full weeks of use I can say Fluke this tech field sense is not ready for prime time and I'm really disappointed in Fluke for the early field sense, works about 20 percent of the time without a ground probe, not much better Use probe grounds while measurements in the field are simply inaccurate. You would think it's just a grounding issue, but I can make sure I have a ground and it's still not accurate. I even bought a new fluke prv 240 fs test block to prove it and the meter works fine with the unit but I take the meter to our panel and try it out and the readings are everywhere, this meter is no better than a t5 -1000, so if you read Think about buying Save your money, the meaning of the field just isn't accurate.