I had a physical version of this a couple of decades ago as a kid. I can find similar products searching for "perpetual calendar". The one I had included a slid

I had a physical version of this a couple of decades ago as a kid. I can find similar products searching for "perpetual calendar". The one I had included a slider to select the month. It also had the day of the week at the top and a small circular peg to place over each day.