As the stationary strip is the only part that can be magnetized (the other two are "amorphous", and not magnetizable), it needs to be properly degaussed to inhibit function. As simply running a strong permanent magnet over a nearby magnetic material is a way to induce magnetism in a material, simply running a strong magnet over the strip may have the opposite effect that you think... it may actually add strength to the bias magnet, and enhance, rather than inhibit function. So unless you have a very powerful portable AC degausser with you (bulky and power hungry), they are harder to defeat than you think! I have found simply paying for the item I want works every time, lol.
