Some years ago I picked up what has always been my favorite hazer, a MBT-300. This machine has a lot of similar units sold under different names I believe, like Antari and such. HZ-300, HZ-350, etc.
After some time it developed an issue where it still worked but it was much much louder. Something was amiss.
Opened it up, and when running the compressor shook a lot. It sits on vibration isolation dampner things, which are basically a screw on each side of a rubber bit.
I looked up the specs from the Mfgr of the compressor, GAST I believe was the company. I got the info about what it should need as far as threading of the feed, but what I ordered would not work.
It turns out the proper thread is M6, not 1/4″. You can find M6 isolation things on eBay and the like. Cost was around $10 for 4, and this fixed the unit. Though it ran $20 since I bought the wrong ones at first 🙂