What is the best brand of teeth whitening strips?

i need a brand that works well but not to hard on my wallet. any advice?
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In addition to bleaching solution, whitening strips are increasingly being used as a preferred tooth whitening product. For instance, you are now able to get your hands on a set of Crest Whitestrips Supreme from any convenience store. The flexible, invisible strips are coated with an enamel-safe tooth bleaching gel. To whiten your teeth, you simply place the strips on your teeth and wear them for about 15 to 30 minutes each day. After a period of about 21 days, you should be able to see a significant difference on the brightness of your teeth. For other effective home teeth whitening solutions, you may wish to read about them here : http://teeth-whitening.my-fashion-house.…
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