Carl's puzzle #004

I built the most complicated way to ring a doorbell

The doorbell needs a puff of air. The bellows went missing.

Puzzle #004: I built the most complicated way to ring a doorbell, with one part in the bin.

The real game, right here. About 15 MB, and it needs a mouse.

Watch me build it
1.

Find what's missing

The missing part waits in the bin on the right.

2.

Put it back

Drag it onto the board. The round arrows turn it.

3.

Press START

If it breaks, the dotted trails show where. Then fix it and try again.