The NB-4L is a rechargeable Lithium-ion battery pack for Canon PowerShot models SD200 and SD300. It"s made to withstand approximately 300 recharges. When shooting with the LCD monitor off, you can expect approximately 400 images when fully charged, or 140 images when shooting with the LCD monitor on under normal environmental and shooting conditions. Similarly, the battery offers about 180 minutes of image playback time.