Model uses M3 screw with round head and M3 nut.
Scale the spacer according to your number of keys and thickness.
The author remixed this model.
Made profiles as thin as hardware allows.
Nut side is 2.5mm thick (nut used is 2.2mm thick M3 nut)
Screw side is 2.2mm thick (nut head is 1.8mm thick)