it's the customer TCM Cincinnati cab used by most fire aparatus makers in 70s and early 80s , some examples

https://www.fire-engine-photos.com/picture/number6993.asp

https://www.pinterest.com/pin/1975-100-ft-pirsch-aerial-ladder-cincinnati-cab-1-of-3-triplets-purchased-truck-1-truck-8-19751991--863917141000278524/


name comes from Truck Cab Manufacturers located in Cincinnati


hence why it can be really hard to ID this trucks