Low Pressure Liquid-Filled Water Review

I have two gauges installed at the entrance to my well - digital and analog. I bought this to use water filters but tested it before plugging the filters in and this shows a low pressure of 7-8psi (more than 10% difference). I can live with that, because I'm actually only interested in whether the pressure drops due to clogged filters - I only have to remember the delta as a guideline. This is annoying, but not an obstacle.

This gauge was replaced with an old/rusty one that didn't work. I'm not sure of its accuracy but it matches the operation of the pressure switch. Pressure relief hole. The Side has a 1/4" thread and I couldn't find a 1/4" PVC connector so I had to use a metal connector which is much more expensive. The easy to read pressure gauge is essential for the correct pressure in the water supply system of the fountain, has worked flawlessly so far and does what it should.

This is a nice easy to read gauge at a very good price. There is very little air inside so it's easy to read even at 50psi (12 hours). However, mine is off by more than 3psi at 30psi and 6psi at 50psi. I dropped the internal pressure and got no change. I've compared it to two other known good pressure gauges that read identical psi at two pressures. I was hoping for 3/2/3 accuracy ratings found elsewhere but was very disappointed. There's a reason a pressure gauge that looks so nice is so…