Zius BK1S/BK2S Plunger Tube and Plunger Rod Assembly

The plunger tube and plunger rod are what actually push air down the barrel every time the BK1S or BK2S cycles, so wear here shows up directly as weaker, less consistent shots. This listing is the pre-fitted assembly — tube and rod matched together — rather than separate parts, which takes the guesswork out of matching tolerances yourself.

It's a straightforward swap for anyone whose stock plunger assembly has worn out, cracked, or is simply due for replacement after heavy use, and it's built specifically for the BK1S/BK2S gearbox so it drops into the same mounting points as the original. Worth keeping one spare if you're maintaining a blaster that sees regular field or backyard use.