GPT 17-Piece Grenade-Style Valve Tool Kit

Replacing valves on a gas blowback is one of those jobs where the wrong tool ruins the part. Most output and fill valves use a slotted head that's easy to round off with a flat-blade screwdriver, and every brand has slightly different valve geometry. GPT's solution is a single handle with five interchangeable valve heads covering the most common gas gun manufacturers, plus a One-Touch Quick-Change socket that also accepts any standard 6.35mm (1/4") bit for general workshop use.

The handle itself is forged from 6061-T6 aluminium with an anodised finish — solid weight in the hand, knurled tactical grip pattern modelled on the MK II hand grenade silhouette so it doesn't slip even with oily fingers. The valve heads are 1144 medium carbon steel, heat-treated to 47 HRC and finished with a non-electroplated physical coating process. That coating matters: traditional electroplating contains heavy metals and solvents, and it can flake off into the gas gun internals you're trying to fix. The PVD-style coating GPT uses is both more durable and won't contaminate your work.

Kit fits in a hard storage case with a lockable lid so the heads don't escape in transit. Comprehensive cross-brand compatibility list below — these cover most of the major brands, though many other models work too since manufacturers have started mixing valve types across their ranges.

Specifications