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http://www.amazon.com/b?node=13819755011

select $ 100 gift card and get $ 5 credit

AND

select $ 75 gift card and add this promo code:0416GCARDS
https://www.amazon.com/Amazon-com-Gift-Cards-E-mail-Delivery/dp/…

you may or may not be qualified.. i got the $ 20 credit by adding $ 100 GC and adding0416GCARDS code since it meets the $ 75 minimum.
Enjoy this exclusive Gift Cards offer:Surprise someone with an Amazon.com Gift Card, and get a $ 15 promotional code to spend on yourself. Just purchase at least $ 75 in Amazon.com Gift Cards in a single order by April 30, 2016, and receive a $ 15 promotional code automatically applied to your account after the qualifying order has shipped. An email notification will also be sent within three (3) days after shipping, confirming your Amazon.com Credit.Enter “0416GCARDS” at checkout to qualify. A perfect present for any occasion, Amazon.com Gift Cards can be sent via email, printed at home, or sent through the mail (with Free One-Day Shipping). Amazon.com Gift Cards are redeemable store-wide for millions of items and never expire. Scroll down to learn how to use your promotional code. Terms and conditions apply; scroll down to learn more.Important Notification:This offer is validONLYto eligible customers. To qualify, you must: (1) purchase the Amazon.com Gift Cards using the Amazon.com account to which you are currently logged in; and (2) enter “0416GCARDS” in the “Gift Cards & Promotional Codes” box when you check out. Additional Terms and Conditions apply; scroll down to learn more.