The Groove Pro HHC-3 hi-hat clutch is the mechanism used to secure the top cymbal of a hi-hat pair to the hi-hat rod while allowing quick on/off movement. It typically includes a locking nut, felt washers above and below the cymbal to protect its surface, and a clamp or threaded section that grips the rod securely. The clutch allows adjustment for cymbal spacing, ensures stable alignment during play, and helps prevent unwanted slipping or loosening under vibration.