PURPOSE: To prevent the occurrence of backlash in use as well by accurately positioning/incorporating a film unit with a lens in a waterproof case.

CONSTITUTION: Pins 29 and 30 whose top ends are tapered are projectingly provided on the inwall of the top surface of a case main body 15. Holes 11 and 12 are formed so as to correspond to positions where the pins 29 and 30 are projectingly provided, on the film unit with the lens 2. When the film unit with the lens 2 is inserted into the opening 16 of the case main body 15, the pins 29 and 30 pass through the holes 11 and 12 and the film unit with the lens 2 is accurately positioned with respect to the case main body 15.