Leslie S5T-R train horn & Doran-Cunningham 6-B Ship horn

This is the variable orifice Leslie S5T-R Locomotive horn compared to the (very rare)1940'S Doran-Cunningham 6-B WWII US Navy destroyer horn **More about the Doran-Cunningham 6-B** This horn is very rare. Mine and Adam's (Airraidsiren on YouTube)are the only 2 that I know of that is still in use. I just recently found out that a ferry called MV Coho possibly has a version of this horn. Only six have been seen in pictures and in person each one having a different configuration. My 6-B is close to 200lbs. of brass, has a 12" diaphragm, measures 36 1/4" long, and has an 18" bell/horn opening. There are markings at the footing of the air inlet "DD416". This is not the biggest horn made; but is considered the best because of it's sound!