Perfect for yards, sidings or main lines Magnet rotates to avoid accidental uncoupling Complete instructions, drilling jig, trackside marker and control knob all included Easily installed in new or existing Code 83 or 100 track Works with most magnetic knuckle couplers Tools Needed (sold separately): 5/32′ 3.9mm Drill Bit 1/16′ 1.5mm Drill Bit