Source google image: https://img.brickowl.com/files/image_cache/larger/lego-brick-1-x-1-with-stud-on-1-side-87087-30-215571.jpg
Lego stud id
Source google image: https://img.brickowl.com/files/image_cache/larger/lego-brick-1-x-1-with-stud-on-1-side-87087-30-215571.jpg