What is a good teeth whitening product?

I want one that I can see results with and that actually works that I can just pick up at walmart, have any suggestions?
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Rembrandt 2 Hour White i doubt they have this at Walmart read the reviews so you know what to expect under $20 http://www.drugstore.com/products/prod.a… Colgate Whitening Fluoride Toothpaste, Baking Soda & Peroxide Whitening Walmart should have this again read the reviews under $4 i actually use this and it gave me good results just how i like it. you should get this anyway to help improve the color of your teeth. peroxide and baking soda are used for whitening; with that combination, you should definitely see results! http://www.drugstore.com/products/prod.a… hope this helps!
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