As you are making a purchase decision, we suggest that you take the time to read some BP511A Battery reviews in order to see what other consumers have to say about the product. Here are some user reviews to help you make your shopping decision:

This battery will give you about 500-1000 shots before going dead. Even if you use the flash often, it won't die easily!! You can always count on this battery, no matter how you use it. Highly Recommended for any level photographer!!
-M. Jimenez (BP511A Battery user review from Amazon.com)

Do not look for cheaper one.

OEM battery works much better and life is more than 3 times longer.

If you take photos in winter, you will regret your choice of cheap brand.

I have bad experience with cheap one. Always Buy OEM battery.
-H. Kwak (BP511A Battery user review from Amazon.com)

I am a professional photographer. Every one of the eight non-Canon brand batteries I have (four different brands)outlived their warranties by only a few days. None of the six Canon brand batteries I own have ever given me any problem of any kind. One of my Canon Batteries is at least four years old and still performs beautifully. I will never buy a non-Canon battery for my Canon camera again.
-T. Gartman (BP511A Battery user review from Amazon.com)

Reliable and quality product. This battery maintains its charge for a very long time and delivers the amount of power necessary for about 300 pictures RAW on my Canon 40D (without flash).
-T. Bayard (BP511A Battery user review from Amazon.com)

I have tried the low cost knock off batteries. Don't waste your time with them. Spend the extra money for a genuine BP511A. It fit's properly, it holds a stronger charge and maintains power levels better in cold/hot weather.
-Tekn0lust (BP511A Battery user review from Amazon.com)

My original battery would not hold charge anymore so I ordered this one from AMazon. It is at least $30 or more cheaper than Canon direct and just as good. Works perfectly.
-E. Murray (BP511A Battery user review from Amazon.com)

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