Abstract: Diving mask comprising a face-piece having, formed therein, one or more openings for housing one or more lenses, means for fixing the lenses inside the face-piece, and means for connecting the mask to the diver's head; said face-piece is formed by at least two portions which are stably connected together, said two portions being respectively made using two materials which are different at least from the point of view of the rigidity, one of the two materials being more rigid than the other one.

Abstract: Buckle for tensioning the straps of fins or the like, having quick and simple fastening and unfastening means, comprising a base part designed to be attached to one side of the shoe of the fin, an intermediate lever hinged at one end by hinge pins to the said base part, and a terminal part which carries at one end the means of connection to the fin attachment strap, while its other end is hinged by the pins at a point on the said lever situated between the end hinged to the base part and its free end, characterized in that the lever possesses on its two flanks, near its free end, two elastically flexible wings, each having a tooth and an outwardly projecting pin, while the base is provided, likewise on each flank, in positions corresponding to the said teeth and to the said pins, with means for engaging with the said teeth, and for housing the said pins.