Buy from Amazon.com : http://fave.co/1CcFDlT
Opteka Battery Pack Grip / Vertical Shutter Release for Canon EOS 450D 500D 1000D T1i XSi XS
Product Description :
Built-in 2100 mAh battery effectively doubles your shooting time
Vertical shutter release also makes shooting with the camera in a vertical position just as comfortable as shooting horizontal
Increases functionality and convenience
1 Year warranty