Serpent SER500904 13mm Shock Cap Seal O-Ring for RC Shocks  [SER500904]

Why the 13mm cap o-ring matters

The Serpent SER500904 Shock 13mm cap o-ring is a small but essential seal used at the shock cap interface. It keeps the shock oil contained and stops dirt entering where the cap meets the shock body, helping preserve predictable shock action.

If the original seal is flattened, cracked, or leaking, replace it. This part seals the cap rather than internal piston joins, so installation only requires removing the cap from the shock. Clean the groove area and inspect the cap face for nicks before seating the new o-ring to ensure a proper fit.

When adjusting springs or replacing shock oil, fit a fresh 13mm cap o-ring to avoid intermittent leaks that could change damping characteristics between runs. Consistent oil level supports reliable setup and tuning.