What is a appropriate tooth whitening gel you can buy at the store ?

I already have the trays I be just wondering if anyone have experience with some whitening gel you can just buy at the store not online I would love some recommendation and where you can buy them at -thanksWhat is a appropriate tooth whitening gel you can buy at the store ?
Crest have some good products out right very soon. Those will work but you have to do it every year for about a week.
You can walk to your dentist's office to buy the professional whitening gel. The stuff you buy at the store isn't strong satisfactory to really work too well. If you dance to a dentist's office they won't charge you for investigational trays again if you tell them you already hold them.