Somehow I lost one of the levers that allows my vents to open and close. So if you spun the little "on / off" knob below the air vent, this wouldn't do anything. Today I decided to take another one out so I could copy the missing piece. Attached is my copy. It took about one hour with millimeter ruler, digital caliper, and paper protractor to get it just right. This will enable you to open and close your air vents if you have the knobs but not the little levers that grab the vents. If you plan to 3D print, I urge you to consider between v3 and v4. I made v4 just to ENSURE it would grab the vent door and click on. Also with my 3D printer I used the stove to soften the clip before pushing it into place (didn't want to take any chances) because it has to flex a lot!1) removed a working vent from the car 2) removed the lever itself from around the vent door 3) measured it carefully, over and over, while adding primitives to my design 4) checked my design against my own vents to ensure they would (a) grab the vent doors without falling off and (b) spin when the knob was turned. It's important to have the following tools to manually copy such an object: 1) digital caliper 2) millimeter ruler 3) paper protractor 4) fine mechanical pencil or ultra fine tipped marker And it's important to have the following tools if you wish to completely hand-finish the part to your own satisfaction: 1) micro torch / soldering iron (hot knife tip) 2) rat tail file