These are parts for automatic roller blinds. These blinds use a 1/2" PVC pipe for the curtain rod with a stepper motor mounted on one end (the other end just idles). The stepper motor is controlled by an ESP8266 connected to ESPHome. The ESP8266 is also connected to a second stepper motor with some speaker wire as an extension cable. This way it can drive the blinds for a pair of windows.

For more information, check out my project on Hackaday!