Long before we had smart phones and digital watches, humankind relied on sundials to keep track of time. Most traditional sundials aren’t as easy to read as the devices we carry with us in our pockets, but this 3D-printed version is designed to display actual digits.

The "Digital Sundial" from the French Etsy seller Mojoptix uses a precise pattern of holes to cast shadows that depict the approximate "digital" time. The blueprint for the seemingly simple plastic wand was made by calculating the angle of the sun as it travels across the sky. It's designed to work between the hours of 10 a.m. and 4 p.m., and updates the time in 20 minute increments.

If you’re not willing to shell out almost $80 to purchase the clock from Etsy, the design files are available for anyone to download and use with their 3D printer at home—just don't forget to set it for your preferred hemisphere. You can watch Mojoptix take you through the process of building a digital sundial in his video below.

[h/t Gizmodo]