On my '40, the only lower hose is 3" at the bottom and 3" at the top that connect to a metal pipe that can't collapse. Prior to finding the pipe at Packard-Seattle (David Moe, who sent several because we weren't sure which one was the right shape), there was, incorrectly, a rubber hose with a spring support in it.
I did not check the parts listed for '39. Perhaps it uses a hose with a spring. The metal hose needed for mine was 341691, with the aforementioned rubber segments and hose clamps (from Restoration Specialties).