What would we do without rechargeable batteries? With photography, these have become extremely handy and popular and common to come in packs of four (four double or triple A’s) when purchasing. A good idea with these packs is to mark each set to keep them together. This way, each set will have similar amounts of discharge when using them and have the same amount of charge time when charging. It is also helpful to keep them separate from others when on live-aboards or dive resorts that use a common table photo area or table for charging.