What are the best over-the-counter teeth whitening kits to buy?

I want my teeth to be whiter without emptying my pockets. what are the best toothpastes/kits that will give a lasting whitening?
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if you are looking for the best teeth whitening, check out this site http://the-best-teeth-whitening-in-internet.blogspot.com/ You'll get a white and bright smile just in 1-2 days and it'll last for 6 months or longer.
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