Up for sale is a 17 inch Menson 0-3000 PSI pressure Gauge. It has 3 brackets on the back for mounting to a flat surface. It's really to large for my settup. It would make a perfect Gauge for oxygen in a Nitrox setup. These test Gauges sell in the hundreds. My price is $75. It's just gathering dust here. I would suggest that it be calibrated or at least compared to an accurate Gauge. If you buy the Gauge I'll throw in a program my son made for calculating Nitrox mixes.