A Mobius Strip is a one-sided structure, usually made by taking a ribbon of paper, giving one end a half twist and gluing the ends together. This one is made by wood turning. Two hollow cylinders are made, one has a cross section of 4cm by 1cm. The other has a cross section of 1cm by 4cm. Each cylinder is cut into two pieces, 270 degees and 90 degrees and re-joined to make a "question mark" shape. The the two "question marks" are joined to make a mobius strip. In the picture, the pieces have not been glued together, so the joins are easy to see.