Sauna Heater Help! - What Cable

[Megawatt]

That's a good question... I bought flexible metal already! Can probably return that and go with cheaper PVC.... in fact I probably have a 3 foot chunk in the office that I can use. Looking for a deep feedthrough to go through the 5/8" cedar, will probably have to put a metal plate there?

Yes every stud you drill through you have to install a nail plate which you can purchase at Home Depot and Lowe’s or your local electrical parts house. Good luck