When not in use, the hydrophones were drawn up into protective "blisters" mounted to the hull.
These photos show the protective blister. Caption of the first photo:
"Copper bottom at last. Port Blister for the housing of 1 of our listedning devices (C) Tube. (SC) Tube housed when under way on starboard side."
Editor's Note: The first photo is the only clear shot of the construction of the protective device for the hydrophones that I have seen, to date.
Thanks to Bob Seiffert, grandson of Clarence Neuner, for submitting the photograph to The Subchaser Archives.