Manloney LLC Universal Foster Quick-Disconnect Coupling Fill Adapter PCP Paintball HPA Air Tool Fittings (8mm Male to 8mm Female Coupling). Converts your existing female “Foster Type” quick-disconnect fitting on your PCP charging hose to a longer female quick-disconnect fitting. This is needed to fill PCP airguns that have a recessed fill port like the FX Airguns do. Quickly snaps on or off, no tools required. Stainless Steel, Working pressure 3000-5000 psi