These silicone o-rings are designed to replace the stock spring that is normally on the front of the hop-up chamber. It will improve the stability of the hop-up chamber significantly by restricting the amount of movement that is caused by the rifle while firing ie. BB loading movements, air nozzle head displacement, and general gearbox vibrations.

The number of rings needed will be vary from gun to gun. Try fitting around 6 first then remove one by one until you have a snug fit.

• Stabilizes the hop-up system
• Consistent hop on the BB
• Uniform FPS from a stabilized compression
• 10 o-rings included can fit up to 2 guns