3 months for free.
You get FREE TWO DAY SHIPPING on all orders - no minimum - OR you can pay $3.99 for overnight shipping.
Only works with purchases from amazon.com or merchants using the Amazon FBA (Fulfilled by Amazon) program.
I don't have a link, if you go to amazon.com you should see the promo. (You may have to search for a pull up a product first!)
Best of Luck,