Legend Nik thank you!No clue what the "FD#X" and "FD##" are used for, nobody I asked was able to figure it out
All of the PRUs are the same no matter the letter EXCEPT the X units. X10 is a Rescue Paramedic PRU. X08, X18, X32, X22 & X45 are all backup designations for the various XR Units if they are short a rescue medic.
MM are the "BHEARD" Units
The AR units are Atom Response units which are essentially BLS Flycars. AR4 for example is placed at JFK Airport and AR31 is in canarise.
What is a "BHEARD" Unit?