DO NOT confuse these trays with the typical "Boil and Bite" tray available everywhere. These Immediate Custom Trays can be used for those who want to start whitening now! These heat formed trays have a thin inner tray that conforms to the teeth with the same accuracy as a custom tray. Althought the fit of the trays are excellent, they stiffer and not as comfortable as the custom fit trays. 3 trays per order.