Use AMEX to save an additional $5 off $15.
Walmart offers free shipping on $50+ orders, so you can order 2 of these to get free shipping.
Or order 1 of these sets and a fantastic deal on an Oral-B toothbrush to get free shipping.
You can also pickup any size order for free at a Fedex or WalMart store. Otherwise $4.97 shipping applies on orders under $50 with ship to home.