Abstract: A diving fin comprises a boot section and a fin section as separate parts which are held in an assembly by a supportive or hinge structure incorporated in the forefront of the boot section and a rear edge of the fin section. The hinge structure comprises an axle or shaft within axially aligned cylindrical sleeves with the shaft coupled to the fin section so that raising or lowering of the fin relative to the boot section is performed by manual manipulation of the fin section. A latch is incorporated in the hinge for detachably securing the fin both in a raised position relative to the boot section and in a lowered position projecting forwardly from the boot section. The latch comprises a fixed radial projection on the shaft engageable with slits formed in one of the sleeves. The slits comprise a circumferentially extending portion that at opposite ends has arcuately spaced apart axially oriented latch slit portions defining the two latched positions of the fin.