Many DSLR batteries have 18500 cell pairs. The Pentax D-Li90 battery is one of them, measuring 20 x 55 x 40mm and fitting snugly enough not to rattle, but there's room to put your finger next to it to pull it out. Additional pieces of foam supplied by the manufacturer are not required. There are little toggle switches on the lid, presumably to help you remember if the batteries are full or low, but they're at right angles to the battery compartment and there's no telling which switch goes with which battery. I don't think it matters though - maybe I'll just put the battery in with the label facing up to indicate it needs charging. When closed, the case fits neatly into a corner of the bag B&H gave me with my K-1 camera. Orderly. I'm not going to comment on how waterproof this case is, and I'm not going to find out. It just looks like a well thought out battery and memory card organizing tool.
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