These Japanese Zip Bags back were bought in 1984, and as well

These Japanese Zip Bags back were bought in 1984, and as well as being fun, they are an interesting example of topology! Essentially a long strip of tough fabric with an attached zip, when you do the zip up, it becomes a useful bag. Depending on the distance from the start of the zip to the end of the strip, 4 different shapes of bag are possible. In addition, you can even combine 2 strips, to make a bigger bag.