This bandana is 22″ x 20″ and has even MORE information than the time travel survival shirt does – including instructions on how to use the bandana itself to invent other technologies like the water filter, the bandage, and the sexy adult handcuff! And if you do ever find yourself stranded in the past, it will be the single most valuable – and most dangerous – piece of fabric in human history.  If you ever get trapped in the past… you’re going to do amazing.

That shape in the middle is the template for building a unit cube – whose weight, when filled with water, will be the basis of the measurements you need to build the other technologies explained on the bandana, up to and including telescopes, microscopes, smelters, electrical generators, and penicillin. At the top there’s instructions for testing if unknown foods are safe to eat – a useful thing to know if you’re stranded before the invention of domestication. Those pictures you see in the at the bottom are ways to transform the rotational motion of a water wheel into more useful motions, like the up-down motion of a hammer or the back-and-forth motion of a saw. Seems pretty straightforward, but it still took humans thousands of years to figure this stuff out!!