Comparison : Item # 502501, Cylindric Retaining Magnets with Smooth or Threaded Stud
Item # 502505, Cylindric Retaining Magnets with Smooth or Threaded Stud
Item # 502509, Cylindric Retaining Magnets with Smooth or Threaded Stud
Item # 502513, Cylindric Retaining Magnets with Smooth or Threaded Stud
Item # 502517, Cylindric Retaining Magnets with Smooth or Threaded Stud