'Flip Clock' is a free plug-in for OBS that easily displays flip-flap clocks, countdown timers, and stopwatches for streamers

Flip clock quickly flips. Retro flip clock changing from 23:59 to 24:00.. Slow motion. Close up.

Flip clock quickly flips. Retro flip clock changing from 18:59 to 19:00.. Slow motion. Close up.

Simulating a flip clock on an Arduino-driven LCD screen | Arduino Blog

Flip clock quickly flips. Retro flip clock changing from 15:59 to 16:00. Slow motion.

Flip clock quickly flips. Retro flip clock changing from 18:59 to 19:00. Slow motion. Close up.