In HC20 Hydraulic Rock Drill (or Hydraulic Drifter) systems, the Seals kit 86684073 is a “critical hydraulic barrier”—it includes all tailored seals for core components (cylinder, valve, piston), working together to lock in high-pressure oil (up to 1800 psi) and block mining debris.

1. Durability: Special nitrile rubber (with anti-aging additives) retains flexibility for the full 800-hour cycle.
2. Perfect fit: Each seal’s size (tolerance ±0.003mm) matches HC20’s components exactly—no on-site modifications.
3. Protection: Blocks dust and oil leaks, extending the drill’s service life.