Like this good. The only problem is the sensor. We have 4 in our hazmat truck with different senor in each

I like this meter its easy to calabrate and use. We have them on every company and with haz-mat.

This is a great tool. It's easy to read . It's a good tool to have .

We use these in the aviation community as well. The PGM-50-5P is the model spec if anyone's interested. It works well, and comes with a cheater card to walk you through the start-up/operation/bump test procedures. the only problem that I have seen is the sensors... They should have a expiration date printed on the sensor itself inside of the detector. Sometimes they dont. Those sensors are shelf life sensitive, and do go bad after awhile. If you have trouble with the bump test, or a reading (O2) just doesnt seem right, take a look at replacing that sensor.