Canon's BP-535 is a lithium-ion battery that works in many of Canon's Optura and ZR-series digital camcorders. Its 3450 mAh capacity gives you as much as 6 hours, 15 minutes of use from one battery (with the camcorder's LCD display turned off). The BP-535 can be charged no matter how much drain has occurred since there's no "memory" effect.
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