Type: Alkaline Voltage: 1.5 V Diameter: 15.6 mm Height: 5.95 mm Best Use By: 2008 Product is Brand New Sealed Also known as: PX625 / PX13 / EPX625 / V625PX / MR09 / MR9 / H-D / HD / RPX625 / RM625 / KX625 / HD1560 / 1124MP / Mallory RM-625R / Eveready E625N / Burgess HG-625R / 4370 / 4371 / V13PX / EPX13 / V625PX / HD625 / PN625 / RM625 / 4625 / 625 / H1560 / HD-D / M01 / M20 / 8930 The MR9, PX13 and PX625 is is a discontinued Mercuric Oxide coin type cell that was commonly used in cameras and is now banned because of toxicity and environmental fears. The original PX625 mercury cell produced 1.35V. There are three possible mercury free replacements for this PX625, PX13 or MR9 cell: * genuine Mercury cell, the PX625, PX13 or MR9 - but they are rare and hard to find. * the equivalent alkaline cell, the LR9 or V625U. * the equivalent silver oxide cell, the S625PX. * the equivalent zinc air cell, the WeinCELL MRB625. * a voltage reducing adapter, the MR-9 adapter and a silver oxide 386 cell The least expensive PX625 replacement is the alkaline cell, the LR9 or V625U. They fit perfectly but, as with all alkaline cells the voltage is not stable, it drifts down from 1.5V towards 1.35V (the voltage of the original Mercury cell) and then lower still. If you use the cell in a camera that needs a steady reference voltage, as the voltage is not steady throughout the useful life of the cells, you need to constantly adjust how you compensate. Because the S625PX silver oxide cell produces a steady 1.55V, you are able to compensate for the higher voltage by a fixed number of stops or by adjusting the ASA setting. There may be as many as two f-stops underexposure by a camera that uses 1.55v instead of the original 1.35v
