The gauge leaks, therefore cannot hold pressure until replaced.As long as you do a small amount of research or know what you're doing this can very very easily be turned into a pressure pot for resin casting. I use it as 50-55 psi and just had to plug one side and buy a new gauge ($8) not a big deal but just a heads up. That being said, I also used thread seal just to be sure there is no leaks. Teaming it with a small compressor, I had a functioning pressure pot w/compressor for ~$220 which is great in my opinion.In short, worth the small amount of work it took to convert it. And it is holding pressure and functioning great.