Abstract: An adjustable fastener includes a male part and a female part, both of which are made of soft pliable, sewable plastic. The female fastener part has three spaced apart openings. Each opening has a broad portion and a narrow portion. The male fastener part has a base with an upstanding riser with a flange at the end of the riser. The flange is dimensioned to fit into the broad portion of each opening in the female fastener part and the riser is dimensioned to fit snugly into the narrow portion of each opening in the female fastener part. The narrow portion of each opening in the female fastener part is rectilinear in shape and the riser is also rectilinear in section. Thus, when the riser is in the narrow portion of an opening in the female fastener part, rotation of the male fastener part relative to the female fastener part is prevented. The back side of the male fastener part is provided with parallel grooves which enhance gripping when releasing the fastener.