Through 6/15, Amazon Student Prime Members who purchase at least $50 in select Father's Day Amazon Gift Cards will get a free $10 promotional Amazon gift card at Amazon. This applies to both physical gift cards and cards delivered via e-mail. Your promotional gift card will arrive via e-mail no later then June 30th, 2014 and must be redeemed by July 31st, 2014. Not a Amazon Student Prime Member? Click here for a free 30-day trial to qualify for this offer. There is no sales tax.