In HC95 Hydraulic Rock Drill (or Hydraulic Drifter) systems, the Slide seat 86789260 is a “silent sliding support”—it’s installed at the contact point of moving components (typically between the piston and shank adapter), bearing lateral forces during high-speed sliding and ensuring smooth, aligned movement. This stability is critical: if the slide seat wears out, sliding components may shift, increasing friction (lowering drill efficiency by 15-20%) or even causing metal-to-metal scraping (damaging the piston or shank, a $3,000+ repair). With over a decade in mining equipment maintenance, I’ve seen generic slide seats fail quickly: most use low-hardness metal (HRC < 35) that wears down to uneven surfaces in 600-800 hours, forcing unplanned downtime.