FMS 1400mm P-51 Main Landing Strut Pin
Main Landing Gear Strut Pin for FMS 1400mm P-51 - FMMSU146
This is the short "pin" which is inserted into the retracts. When this pin is inserted into the retracts, the FMS main landing gear strut (part SU118) slides over the pic. SU118 also includes this pin (it is at the top of the strut and held on by a set screw).