Paranormal Equipment....store bought

Just like orbs, there is a lot of controversy on what is the best equipment to use. Lets start with the store bought equipment. It all depends on what you are looking for (lights, sound, digital read out, etc.). MEL,  KII to name a few are all good products but.....with my electrical background and dealing with meters daily to protect me, I am concerned. If all you are looking for is a change in magnetism, these work great! As you know, spirits can manipulate the magnetic field and these see that. Are the readings we get from these as far as mG correct? Does it matter? To me it does. With my electrical meters, I send those in every 6 months to get certified and re-calibrated for accuracy. There is no re-calibrating of the KII, but I bet you could contact Gary Galka, the inventor of the MEL and get it done if desired. He is the owner of Pro-Measure.com and he makes meters for a living outside of the paranormal world. Bottom line on the store bought....You get what you pay for so don't go cheap.