This 6V battery to replace the battery that comes my Hörmann garage door opener. After unpacking I immediately measured the voltage, also out of interest how high the voltage at a "fresh" 6V battery. To my great surprise, the tension of these Duracell battery was just 5.81V, ie well below 6V. Even the old China battery, the work done nor their service in the garage door opener was after 1 year service still about 6.1V. The specified "Best before" date is still nearly 3 years in the future, so it can not be it also. Absolutely defective product and not to be recommended!