Vktech 12Pcs AAA to AA Size Cell Battery Converter Adaptor Holder Case Switcher~Small size, Easy to carry Fine workmanship, standby specification, 1xAAA battery can replace AA battery to use Nothing complicated, just stick the AAA battery in the converter and it's the same as a AA battery Size: Approx. 5 x 0.9 x 1.3cm (H*Inner D*Outer D) AAA to AA Battery Holder is a gadget to keep close at hand, at home, at the office, at the campsite, etc 100% brand new and high quality