This model perpetual flip calendar really works! And it is easy to use. All it takes to change the date and day of the week with one flip. With 15 double sided date tiles, 7 week tiles, 12 month tiles, and room for 4 year tiles, this calendar will never lose track of time. This build is of a Perpetual Flip Calendar, these small metal calendars were invented in the 1920's and are still useful and accurate to this day, so I made a working model. This calendar is divided into three sections, the first spins and houses the specially stacked date tiles. The second section has the week tiles witch are spaced and connected to the first section so they are adjusted when the date is adjusted. The third section houses the month tiles and the year tile and a knob to change the month at the far end. With 988 pieces this challenging but rewarding build makes a great piece of home decor.