Came across this fairly common WW2 Flare / Signal Gun made by EVCC " Eureka Vacuum Cleaner Corp " I believe this could be a Line Thrower made by them but have yet to find another like this. I came across a patent by RF Sedgley flare gun modification which looks similar to this gun ( pdf file below) . The extension measures 6 1/2 " long from the end of the original flare gun. The barrel opening is 1/2" Dia . Any thoughts.......Thank You Bob LineThrower.pdf