The best
I use 20% once every few weeks. When I get lazy and skip a month or 2, I reach for my 35% - 2 or 3 days in a row.  When I  really need an instant boost, one or 2 treatment of 45% easily does it. It's best to invest in bleaching trays. They last forever. Opalescent is what we use and recommend in a dental office.  It is what works.
Rating: 5 stars