I bought 2 of these 4-packs and Duch performed the initial charging with different chargers. After 5 days without use I wanted the batteries inserting in a digital camera, and realized that they were empty. Even after 5 charge / discharge cycles, the behavior has not improved. Here perhaps there must be a production fault and I'll return the battery to Amazon, since I find on the website of the manufacturer no information about the warranty processing or a hotline. For a brand manufacturers this is very below average and I will refrain in future purchases of this brand.