The Pringles 2011 Mail In Speaker Can Promo is a rare and hard-to-find portable speaker designed to clip on top of a Pringles potato chips can. The Pringles can speaker is a simple speaker/amplifier assembly designed to snap onto the top of a Pringles can. It's powered by three AA batteries, packs a single 2-inch driver, and has a hard-wired cable tipped with a 3.5mm stereo plug. Plug it into a smartphone, an MP3 player or a computer, flip the power switch, and you've got - well, sound. Pringles' magnanimous deal was simple: Send in your receipt from the purchase of four Super Stack cans, and Pringles mails you a speaker. For free. You didn't even have to pay shipping.
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