The Canon BG-E2N Vertical Grip/Battery Holder adds a vertical
The Vivitar Power Grip holds 2 LP-E8 batteries, providing twice
The Vivitar Power Grip holds 2 LP-E5 batteries, providing twice
The Vivitar Power Grip holds 2 EN-EL14 batteries, providing
The Vivitar Power Grip holds 2 ENEL3E batteries, providing you
This battery grip doubles battery life with a rechargeable