nitrox stik

Hi, Recently we decided to build a Nitrox stick to be able to fill Nitrox up to 40%. All this is being fed into a compressor that produces 400l/m. We have some medical flow regulators that go up to 18l/m but that isn't near enough to get a decent Nitrox mix. Some calculations show that we...

I'm building a Nitrox Stik using Max Air 35 gas compressor and having a hard time deciding which reliable flowmeter to get, what should I look for in a flowmeter and your recommendation. Thanks