The eneloop D-spacers allow you to convert your AA batteries into D-size batteries so that you can use in devices that accept D batteries.  The spacer comes with 2 AA batteries, which are simply inserted in the bottom of the spacer.

Catalog Number

K-KJS1MCA2BA

Specifications

Dimensions:8″ x 4.75″ x 1.375″
Weight:2.82 oz.
Temperature Range:32°F to 95°F
Accessories:2 eneloop AA batteries

2 C-Spacers