Basically galvanized anything is taboo Here is a link to a aluminum 90's for not much money.
Looking to attach my ammo can w/ AMNPS to my MES but can only find galvanized 90deg adapters. Is this an issue? I've looked everywhere and can't find stainless. It won't be in direct contact with flame so I would think it's not an issue.
Thanks,
EQ
I wouldn't worry about using any galv. fittings for a mailbox mod. You won't be generating enough heat to get the chem. reaction to release the bad gasses. If you were you would not be able to use these fittings for the purpose they were designed for, furnace & water heater exhausts. They burn much hotter and people are not dropping in their basements.