Crest teeth whitening strips?

hi are these teeth whitening strips good !! and how much of a difference did u see
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They do work really well. I would use the 7 day premium ones so it won't take so long. It gets aggravating doing them for 14 days. Depending on how white your teeth are now, it probably won't make them super bright white, but it will bring them up 2-3 shades. I do a box twice a year to get them nice and white, then use Arm & Hammer Whitening toothpaste in between. My teeth stay white all year round.
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