One of the most popular products to fly off the digital shelves during Prime Day is back on sale for Amazon's Big Spring Sale.Crest 3D Whitestrips are available right now at a fraction of the cost during the March shopping sales event. This is notable as the product is known to be a favorite among Prime members during events like Prime Day. During Amazon's October Prime Day, the Crest 3D Whitestrips, Professional Effects were among the best-selling items in the United States. And now in a first-of-its-kind sales event for Amazon, the same product is seeing a markdown, as people can get the pricey Crest 3D Whitestrips, Professional Effects pack for 13% off their original price. That’s not all, though. A 10-count pack of the Crest 3D Whitestrips is also on sale at 17% off its original price. A 20-count pack of the Crest 3D Whitestrips Radiant Express is 53% off its original price. But Crest isn’t the only brand seeing their teeth whitening strips marked down for Amazon's Big Spring Sale. Here are some other brands we found.Save 54% on the Teeth Whitening Kit Gel Pen Strips from OllmSave $4 using a coupon on the Lumineux Teeth Whitening Strips 7 TreatmentsSave 10% on the Lumineux Teeth Whitening Strips 21 Treatments Save 26% on the Zimba Teeth Whitening Strips