Features:A medium-duty commercial and residential grade sliding door hardware series ideal for single and by-parting installations.Applications include: doors between rooms, closet doors, cabinets, storage walls, and partitions.For doors 1-3/8" and up weighing up to 150 lbs., optional nylon wheel carrier up to 100 lbs.Precision ball-bearing wheels ensure a smooth, quiet and long lasting performanceHeavy duty aluminum I-beam track; jump proof designPivoting rocker arms ensure track-carrier contactBall and socket suspension compensates for minor header misalignmentLock nut ensures permanent positioningSerrations in apron permit positioningSide MountPackaged set includes: 8' track and hardware set GR72-138