Grill tiles and levers
Grill tiles and levers can be used to create a very small 180 degree inverted stud rotation. The technique isn't very sturdy, so it's best used for details.
To find the different pieces needed for this technique you can search LEGO's online Pick-a-Brick for the design ID's. We link other market places directly on each individual piece page, which you can find below.
Did you know that Swooshable has a YouTube channel? Subscribe to it to see more of my hands and learn cool LEGO techniques.
Assembly is easy: two grill tiles wedged around two levers.