plumbing - How do I Loosen a Stuck Threaded Brass Fitting? - Home Improvement Stack Exchange

I’m about to replace some of the brass water pipes to PEX in my basement. I bought an adapter fitting at a plumbing supply store(picture 1) and cut the cold water pipe(picture 2). I tried to remove

plumbing - How do I Loosen a Stuck Threaded Brass Fitting? - Home Improvement Stack Exchange

plumbing - How do I Loosen a Stuck Threaded Brass Fitting? - Home Improvement Stack Exchange

plumbing - How do I Loosen a Stuck Threaded Brass Fitting? - Home Improvement Stack Exchange

plumbing - How do I Loosen a Stuck Threaded Brass Fitting? - Home Improvement Stack Exchange