The GLO whitening kit that you see in the store is different in 2 key ways. First off the light that is used in the retail version is about half as warm and intense as the light used in the GLO Professional System (GLO PRO). Secondly the gel that is used to whiten your teeth in office is 30% hydrogen peroxide as opposed to the gel bought at the stores which is 3% hydrogen peroxide. The take home part of GLO PRO uses a 9% gel vs. the 3% you can buy in the stores. GLO Professional has told me that the in office/take home procedure is about 80% stronger than the product that you would buy at Sephora.