Which is the best affordable Teeth Whitening products?

Hi everyone, i just wanted to ask, what are the best, most effective, and affordable teeth whitening products that can be purchased from a local pharmacy (not from any websites)? There are so many different kinds, i don't know which ones are good or not, which ones work or not, so yea i just wanted to ask for you opinion. P.S. I was thinking about trying the Listerine whitening pen because so far from what i have seen, it the cheapest teeth whitening product, have anyone tried it before? if so, how did it work out? Thanks
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I personally just used the "bellaBrite" system and found it to be the most effective product for me and for a very reasonable price. They also let me enjoy a short free trial of the product and I was told that if I wasn't completely happy with the product I could send it back at anytime and not pay a penny. As for the actual results, my teeth have never looked better. I feel so much more confident in my smile and am not afraid to do it anymore. I also have enjoyed a better response from the opposite sex, and several girls have even asked me to share my secret to whiter teeth with them! Overall, the product was really effective, at least for me, and the cost was comparable to most teeth whitening products you might see at your local store. If you are interested in buying it, here is the link: http://tinyurl.com/ycvh7gx
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