PPM Meter?

[Slowitdown]

Hello everyone,

Great site! I have been reading here for about two months now. I have a question. Recently I learned about PPM and the PPM Reader. It is very confusing. Can someone please explain how to use one and what I have to look for?

 

[woodsmaneh]

https://www.thcfarmer.com/community/threads/why-ppm.7215/