Review on 🌊 Stainless Steel Malida Water Pressure Gauge for Aquarium Meter & Reverse Osmosis System Pump, 0-1.6MPa / 0-220psi, 1/4" Size by Denise Davis

Size of diameter is good. Much more than small on my Rodi device. Use the usual amount of thread tape and screw into the fitting provided. Noticed water seeping around the thread after a few minutes. Doubled the amount of thread tape and reinstalled the jig. I've also noticed water seeping in after 5 minutes. Harbor Freight happens to have a set of Viton o-rings, so they put 2 o-rings (a larger one and a smaller one that fit the larger one) in the bottom of the fitting and used triple the amount of thread tape. I pressed the gauge against the o-rings and after 15 minutes there were no more leaks. If you buy this gauge, you may have to go the extra mile to prevent it from leaking, or you may end up with one that seals properly the first time. Just a note that the line pressure was 85psi