Malida Water Pressure Gauge Stainless For Aquarium Meter 0-1.6MPa 0-220psi Reverse Osmosis System Pump With 1/4 Pressure Gauge with fittings for quickfit connection to 1/4" (6mm) Water Pipe Pressure gauge for use with reverse osmosis systems, aquarium discuss marine systems and all water filter systems The Water Filter Men Pressure Gauge for Aquarium RO Reverse Osmosis System with 1/4 Used a lot on the water pipe prior to your reverse osmosis system / aquarium ro / other Stainless Pressure Gauge 220 PSI with fitting