Demagnetizer Pro-Craft Large Orders over $100.00 are usually shipped within 24 hrs of receipt (excluding weekends). The estimated delivery dates showing on Amazon are usually delivered much sooner than the dates shown. 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). Free Shipping!!! Used by Professional Jewelers