Abstract: What is described is a buckle structure comprising a female part (12; 212) and a male part (14; 214), each having means (22; 24?, 24?; 222; 224?, 224?) for connection to corresponding elements of articles of clothing or accessories to be fastened or coupled together. The female part (12; 212) is provided with a cavity for the insertion of an axial tab formation (30; 230) carried by the male part (14; 214), which has transverse seats (36a, 36b; 236a, 236b) on its opposite lateral edges (34a, 34b; 234a, 234b) for engagement by fastening members (72) of an operating mechanism (40; 240) associated with the female part (12; 212), these fastening members (72) comprising a pair of teeth located on opposite sides of a longitudinal direction of coupling of the buckle, which form between them a transverse aperture (74) for the insertion of the tab formation (30; 230).

Abstract: An adjustable clasp comprises a retainer body having an elongate cavity within which slides a strap having saw teeth. The retainer body includes a main generally non-deformable body from which extends a flexible tongue provided with pawls projecting into the cavity to engage the teeth of the strap, and at least one resilient wing facing the flexible tongue and engagable under pressure to disengage the pawls from the teeth of the strap. The retainer body has guide members on the main portion and second guide members close to the opposite end of the main body, to maintain the strap close to the pawls. The second guide members include a contact portion extending from the resilient wing at its end opposite the main portion of the retainer body.