The C40N is a battery grip for the CANON EOS 50D/40D/30D/20D DSLR cameras, which can hold two battery packs BP-511A or six size-AA batteries.
It is equipped with a vertical-grip shutter button, command dial, AE lock/FE lock, and AF point selector button to enable shooting in the same fashion as a horizontal grip.
Major Specifications
Type: C40N Pro
Power Source: (1) one or two BP-511 battery packs
(2) 6 pieces AA-size batteries
(3)AC Adapter Kit ACK-E2
Dimensions: 142.7x110.5x75.7mm
Weight: approx. 315g (not including battery packs and battery chambers)