Contains 4 syringes of Opalescence PF 15% carbamide peroxide based gels. Delicious mint flavored. Moderate whitening for normally sensitive teeth. Nothing freshens up your appearance like a whiter smile. Opalescence is the first ADA accepted, syringe delivered, take-home bleaching gel. The patented formula has sticky, adhesive properties, which produce results in days rather than weeks! Those glorified toothpastes at the grocery store just can't give you the whitest possible smile, only your dentist can.