Allen's Battery

The Allen's Battery (or Professor Allen's Miniature Galvanic Battery) is an electrotherapeutic medical medallion, promising to generate a healing electric current in the wearer, produced by the reaction of the varying metals constituting the battery with the wearer's skin (as a galvanic response). It is identical in design to Boyd's Battery and the Sagendorph Battery, with "Allen" stamped on it in place of "Boyd" or "Sagendorph", and was sold primarily in Australia and New Zealand by Allen himself.