What is a good brand of teeth whitening strips?

I have heard that using things like crest white strips breaks down your tooth enamel. Is there any brands that would be better?
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It will damage your enamel, I've used it with no luck. Now I'm using teeth whitening toothpaste plus a product which I found recently and they work like a charm. I'm using crest teeth whitening toothpaste. Also if you're interested in the product which helped me a lot Hope this helps
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