Power Inflators should be Maintained, but that requires being able to disassemble the Inflator.
The DSS Inflator Service Tool provides three functions; A 1/2 in. hex wrench for the QR nipple, a special spanner for removing the Cartridge Valve, and a 1/4 in. Hex for removing the spool from the Cartridge valve.
Small enough to fit in any Save a Dive Kit. Precision Water Jet Cut from 304L Stainless Steel, deburred. Fits most generic Power Inflators