While the 2.5L OXA Alkaline Jug (link below) is a favorite, you can't get replacement filters from OXA. They fit the jug and appear to be of comparable quality, preventing the jug from becoming obsolete.
NANPU 1/2" NPT Air Drying System - 5 Micron Particulate Filter, 0.01 Micron Coalescing Filter, Air Pressure Regulator Combo - Semi-Auto Drain, Poly Bowl W/Metal Gauge
23 Review
NANPU Air Drying System With Double Filters And Pressure Regulator Combo For Clean And Controlled Air Supply
18 Review
NANPU 1 FRL Air Filter Regulator Lubricator Combo With 0-150 Psi Gauge, 5 Micron Brass Element, Poly Bowl & Semi-Auto Drain - Metal Bracket Included
20 Review
Filter under the sink Aquaphor Favorit ECO silver
20 Review