Piaggio metal ignition lock cotter block.

This is the part that sits inside the steering column ignition lock between the ignition barrel and the electrical switch at the back. It's also the piece which actually locks the steering shaft when the steering lock is on.

Genuine Piaggio part.

NOTE: there are a couple of variations of this item- this is the larger one where you can push the ignition key in to release something e.g. glovebox, seat, fuel cap cover etc.
See also this item....

Piaggio 1B006291, 298903