VEVOR Air Compressor Filter Regulator, 3/4" NPT 3-Stage 5μm & 0.3μm & 0.1μm Air Drying System with Micron Filters and Desiccant Dryer, Auto Drain Air Compressor Water Separator 175PSI Max Pressure

Dear Customer, Thanks for your inquiry. After using up the four bags, you'll need to buy more at the market.

The first copper filter cartridge is reusable; if it gets dirty, you can remove it and rinse it with clean water. As for the second red filter cartridge, an extra one is included in the package. There are 4 bags of desiccant. If this answer does not resolve your issue, please contact us again for assistance.

Hi, O-rings or dedicated maintenance kits for this unit are NOT available for separate purchase. Only the complete unit and filter elements are listed on the product page; no O-rings or seal repair kits are offered.