The present invention relates to a method for handling or transmitting encrypted user data objects. The magnet may be a portion of the cutting head made from a magnetically permeable or permanent magnetic material, a portion of the drive shaft made from a magnetically permeable or permanent magnetic material; a separate magnet between the cutting head and the drive shaft, a portion a magnet on a sheath covering the drive shaft. The uranium-235 is present in an amount such that it constitutes from about 0.