CLINICALLY PROVEN TO WHITEN TEETH UP TO 8 SHADES IN JUST ONE WEEK. The Nupearl® Teeth Whitening Pen is so effective that it’s recommended by dentists! This advanced whitening gel delivers maximum results in a convenient, easy-to-use pen. Just brush on – no uncomfortable trays, no downtime. The gel goes to work in seconds for visibly whiter teeth. Peroxide-free formula is gentle on teeth. .08 oz.