This is a replacement for a standard 5/8" window sash guide, also known as a window sash cam. Originals are injection molded in a type of nylon, but I realize not everyone is set up to be able to print in nylon. I printed these in ABS, but if yours will be exposed to UV light (older, non-UV blocking windows) I would recommend PETG or ASA. Do NOT use PLA, it will not hold up! I recommend 100% infill for extra strength.

Measurements are shown in the screenshots, in metric. Standard measurements are around 1 7/16" x 5/8" x 1/2" (LxWxH)