Comparison : Item # 01-66-40, 66 Series: .156 Board Hole x 6-32 Threaded Chassis Hole
Item # 01-66-60, 66 Series: .156 Board Hole x 6-32 Threaded Chassis Hole
Item # 01-66-80, 66 Series: .156 Board Hole x 6-32 Threaded Chassis Hole
Item # 01-66-100, 66 Series: .156 Board Hole x 6-32 Threaded Chassis Hole
Item # 01-66-120, 66 Series: .156 Board Hole x 6-32 Threaded Chassis Hole