I have been picking up a few Eneloop batteries here and there building my supply. I was in Costco picking up some Crisco and a few odds and ends when I seen an open green folding case with eight AA batteries, two AAA battries, 2 D cell, 2 C cell and charger from Eneloop for 29.99. The C ad D cell batteries looked funny as they had what appeared to be holes in the bottom. I turned the package over and my first reaction was "NO S*&%". The D and C cells are designed to accept one AA battery. Any AA battery. While a AA battery will not last as long, it is a great idea and another backup just in case. Sold and I'll be heading back to pick up a few more for Christmas presents. Just thought I would share.