on purchases of $34.99 or more and
Free Standard Shipping on purchases of $34.99 or more applies in the U.S. only. Free Returns in the U.S. and Canada. Large, oversized items and products delivered by special or white glove carriers are not eligible for free shipping or free returns. Free returns are not applicable to final sale/non-returnable items. As always, check the deal's Fine Print for restrictions.
I have used these for 5 months now, and they are just as good as the very high priced Oral B heads. I got the 4 pack just to try them out, and I am getting the 20 pack because they work so well. They have 4 colored rings you can put on the bottom of each head so you can tell which one is yours and share the rechargeable handle with other family members. The floss-action works so well I only use string floss once a week and even then there is no plaque. Dental cleanings are a breeze.