For the Canon EOS 40D D-SLR is the redesigned high-capacity Battery Grip BG-E2N, which offers high-volume shooting and easier vertical shooting.
Compatible with up to two BP-511A battery packs or a set of six AA-size batteries, the battery grip approximately doubles the number of shots that can be taken, compared with the battery power of the Canon EOS 40D alone.
The Canon BG-E2N grip features new sealing material around the battery compartment to better resist water and dust. The new model replaces the original BG-E2 grip and is compatible with the EOS 20D, 30D, 40D and 50D models.