Extremely sensitive, 20 mm diameter, compass is useful for detecting presence of magnetic field in watches, instruments, and other components. Sold by the box of 12 only.
Demagnetizes or magnetizes parts, tools and meters. To demagnetize, simply hold object in the center of the opening with button depressed for 3 or 4 seconds. Slowly withdraw object in a straight line and release button. To magnetize, hold the part or tool against the inside of the opening and press the button for 4 or 5 seconds and release. Opening is even large enough to accommodate cassette tapes for quick erasure. Opening measures 3" x 1-1/2" (76 x 38 mm).