equip people orp meter and ph meter

got these from my brother who no longer has a tank, but i don’t have any knowledge of them and would rather not have any more electrical plugs, wires to worry about.
I have not plugged them in and i’m unsure if they need to be in water to do so. have very little idea of their worth ??? someone was selling the orp for $49 and the ph for $100. i don’t really care, if there’s someone who can use them, great.
any interest? trade for almost anything that’s alive. no reasonable offer refused. will accept cash, but would rather trade.




Intersted in both, you have PM