H2ODYSSEY Yoke Pressure Tester - Scuba Diving Gauge

I can't understand how they send me items that arrive extremely late and gauges that don't work.

I purchased this a while ago and put it with my dive gear without ever testing it out. I'm diving this weekend and thought I'd check some tanks. This gauge is reading about 600psi low. I checked and double checked with multiple dive computers. I had a more expensive one in my cart, and then decided to save a few bucks and go with this one. Big mistake.

Not only is this gauge inaccurate, it is inconsistent. One time it will read 200-500 lbs light, the next it will read 300 lbs heavy. I should have listened to the other reviews. I returned this gauge.