In HC95 Hydraulic Rock Drill (or Hydraulic Drifter) systems, the Adapter drain 86788114 is a critical “oil management component”—it’s responsible for safely discharging excess or contaminated hydraulic oil from the system, preventing oil overflow (which risks damaging electrical parts) and ensuring the oil level stays within the optimal range for pump and valve performance. With over a decade in mining equipment maintenance, I’ve seen generic adapter drains fail frequently: most use low-quality thread machining that leads to oil leaks (wasting costly hydraulic oil) or stripped threads (requiring reworking of the drill’s oil tank—an extra $1,500+ in repairs). Worse, generic adapters often crack under vibration (common in mining) after short use, causing sudden oil loss and forcing immediate drill shutdown.