Double coupon! Amazon has the 4-Pack Colgate Total Whitening Toothpaste Gel (Clean Mint, 5.1oz each) for $12.78 - 15% off coupon (click here) - 20% off coupon (check "Save an extra" box, eligible on first S&S order for this product) - 5% off with Subscribe & Save (can cancel at any time) = $7.66 with free shipping on $35+ or with Prime. Roughly $1.92 per tube vs. $3.98 at Walmart.