
I have used this to add a deionizing filter to the system but the elbow will leak no matter how tight I made it. Luckily I had to use some spare rubbers to tighten it up. I should have noticed that there were no pads in the photos.

NANPU 3/8" NPT Compressed Air Filter Regulator Combo Piggyback, 5 Micron Brass Element, Poly Bowl, Semi-Auto Drain, Metal Bracket, 0-150 Psi Gauge
26 Review

Filter under the sink Aquaphor Favorit ECO silver
20 Review

NANPU DFR-02 1/4" NPT Air Drying System - Double Air Filters, Air Pressure Regulator Combo - Semi-Auto Drain, Poly Bowl
20 Review

π§ NANPU 1/2" NPT Compressed Air Filter Regulator Combo Piggyback with Auto Drain, 5 Micron Brass Element, Poly Bowl, Metal Bracket, and 0-150 psi Gauge
18 Review