Black Friday Deal. Amazon has the 4-Pack Amazon Basics Alcohol-Free Anticavity Fluoride Rinse (18 Fl Oz each, Mint) for $7.66 - 5% off with Subscribe & Save (can cancel anytime) = $7.28 with free shipping on $35+ or with Prime. Helps prevent cavities and tooth decay, and helps strengthen teeth. $1.82 per bottle.