I have a Alpha Meter. I modify it into a plugin sensor version. It works great and easy to use. I improve the thermalpile with a stand that is easier to stay still on the table. I believe some people are struggling in setting up that little heatsinked sensor. I also have a green laser it puts out over 150mw. If needed I also have cr123 and charger. This green laser has thin beam and it burns :eg: . Alpha Meter trade value around $160 and greenie is around $70.