Airbox Screws V4 893132
Fitment - RSV4 09-21, Tuono V4 1100 15-21, Dorsorduro 1200 10-16, Caponord 1200 14-17
Genuine Aprilia screw, part number 893132, item number 23 in the diagram.
These are what hold the velocity stacks in place within the airbox which means you have a smooth and uninterrupted flow of air into the throttle bodies thus creating oodles of power.
The heads can sometimes become worn or they are cross threaded when inserting which in turn strips the thread and so these are the only replacement part to use.
They are also used in other areas such as on the swingarm of the Dorsoduro.