19-Tooth Polygonal Piston SR25/R85 Blue – SHS

SHS 19-tooth piston for SR25 and R85/L85 AEG replicas, with a polygonal body in glass-fibre-reinforced engineering plastic and a full-length steel rack. It is the right replacement when the stock piston's teeth are worn, or when you want a tougher mechanism on these platforms, which require a dedicated 19-tooth piston.

Features and technical specifications

• Manufacturer: SHS
• Manufacturer code: TT0087
• Type: 19-tooth piston for SR25 and R85/L85 gearboxes
• Body: glass-fibre-reinforced engineering plastic, polygonal profile
• Rack: 19 steel teeth, continuous along the full length
• Compatibility: SR25 and R85/L85 AEG replicas
• Not compatible with: A&K SR25 gearbox
• Colour: blue

Operation

The polygonal profile reduces the piston's friction inside the gearbox and, together with the glass-fibre-reinforced body, makes it stronger. The steel rack runs without gaps along its full length and withstands wear far longer than plastic teeth.

Installation

Fitting it requires opening the gearbox, which is also the right moment to check the piston head, spring and spring guide. For the A&K SR25 gearbox, which this model does not fit, the yellow SHS TT0040 version is available.