how therm a-rest-sleeping-pads are made

[raphael]

http://indefinitelywild.gizmodo.com/how-therm-a-rest-sleeping-pads-are-made-1703679138

In the early 1970s, two Boeing engineers used a sandwich press to put a slice of foam between two pieces of airtight fabric and invented the self-inflating sleeping pad for campers. Therm-A-Rest still uses that basic principle today, just the sandwich machine has given way to an entire factory in Seattle. This is that production process today.