Fall river fd - " special service unit " - auxiliary fd

[agent yo'range]

https://fallriverma.gov/departments/public_safety/fire_department/divisions/special_service_unit.php

3 vehicles - mobile command post / rehab / lighting etc

iirc special service unit is an old ISO term - maybe a ladder truck
with no steel aerial - maybe a heavy rescue that responds to structure
fires - etc - fd gets ISO credit for these units iirc