Fraudulent counterfeit versions of these flashlights have been sold, most of which incorporate coin-sized non-rechargeable lithium cells "hidden in plain sight". The expensive supercapacitor is omitted from the internal components. In some of these fake designs, the "magnet" is not a magnet or the coil is not connected, and no electricity is generated when the device is shaken. These fraudulent flashlights eventually become useless, since their internal batteries cannot be recharged or replaced, and the case is often permanently glued shut.