This is a Marie Claire Sport wristwatch. It has a date and day display function. The day of the week cycles, but it's not a perpetual calendar; the day needs to be adjusted at the beginning of the month, which can be easily done with the second crown (below the main crown). This is a practical and excellent piece. The strap has a unique lug shape, so replacing it with an aftermarket one might be difficult. The current size is about 16 cm. To keep the package under 3 cm thick for shipping, I will detach one side of the strap and individually package the spring bar.