What is a good teeth whitening system that can be bought online?

What is a good teeth whitening system that can be bought online? I got trays made a couple of years ago and went through a bleaching system, kind of half way. I'm wondering what a recommended brand of bleach or peroxide is. I paid like $200.00 for the trays and kind of wanted to get something stronger than Crest or an over the counter, any suggestions
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You paid $200 just for bleaching trays ??? You got ripped off ! Do yourself a favor and don't waste any money on bleaching products for your teeth. The over the counter stuff is not strong enough. Go to a dentist if you have to bleach your teeth. Keep in mind that crowns, caps, fillings and other dental work will stay the same color, they will not become lighter. Look, people don't know that teeth are living organs (having blood vessels and nerves), they're not just pieces of bone stuck in your gums... The colour of the tooth comes from within (the dentin), the enamel is the outer layer that covers the dental crown and protects it. The bleaching affects the enamel creating the temporary illusion of "whiter teeth". Ever wondered why you need to bleach AGAIN ? Oh, let's mention the hypersensitivity you're left with after bleaching, and doesn't always go away... Working in a dental office I could have this (bleaching) done for free (zero, zip, zilch, nada) but I choose not to do it !...If people only knew...
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