CleanStep Indoor Adhesive Mat With 30-Sheet Starter Pad, white frame / white sheets, 25 1/2 x 31 1/2. Dirt-smart doormat strips dirt from shoes and wheels at the door. 30-sheet disposable starter pad attaches to a nonskid, reusable frame. Disposable sheets are coated with a specifically formulated adhesive that aggressively traps dirt particles and contaminants. Especially effective against dust and other small particles. Remove dirty sheet to uncover clean layer underneath.