Elevator Emergency Stop Button to replace the one that got sheered off in a move. 

When the old button got broken, we looked for a replacement and they cost roughly $150-$200 and could only be installed by a certified technician. 

The mechanics of replacing this on the switch are something for their own project video and so having a certified tech do it might not be a terrible idea. But if you are brave beyond reason like me then you'll pull the whole thing apart and find that you can do it in 2-3 hours. 

Print this one with 100% infill for obvious reasons.