Ships from the United Kingdom. Brightest 1 watt LED Upgrade for Petzl Headlamps and other lights, lanterns with incandescent MES-E10 screw based bulbs. Fits BMW Glove Box flashlights, Conger railway lanterns, Viewmaster 3D viewers, battery Instabulbs etc. 4x longer battery runtime and long life bulb saves money; pays for itself . Uniquely non-polarity; will work whichever way the batteries are connected or if they are reversed in error. No need to re-wire which is not always possible. Most LEDs do not do this. Versatile: use in equipment with 2, 3, 4, 5 or 6 AAA, AA, C or D cell alkaline, rechargeable or 3LR12 batteries. Sealed Lead Acid batteries – Voltage range: 2v to 9v DC/AC Easy to fit, a straight swap – utilises the original reflector. Focused beam; beam patterns will vary depending on the type of reflector used. Overall bulb length: 22mm. Diameter: approx. 9.8mm at the top and 9.2mm at the bottom screw part.