Baking soda & peroxide, With microbeads and whitening crystals. Better value. Base not included. The Baking Soda & Peroxide Reaction: In a dual chamber dispenser, baking soda & peroxide are kept separate. When you brush, the two sides react and release powerful oxygen bubbles. Bubbling action formula breaks down stains and leaves your teeth noticeably whiter. With microfine whitening crystals for breath freshening. Helps prevent tartar build-up. Refreshing clean taste. Strengthens teeth and fights cavities. Easy-to-Use Refill: When your Mentadent pump is empty, simply remove the empty cartridge and insert the refill. It's easy, clean and convenient. Note: This refill cartridge must be used with a base from a full size Mentadent; it will not function as a stand-alone unit.