Abstract: A fastening device for securing, for example, two pieces of fabric together comprises an outer body and an outer body secured in the outer body for rotational and axial movement relative thereto so that the inner body can move outwardly and inwardly of the outer body. The inner body carries a securing element in the form of a hook or spiral so that when the inner body is moved out of the outer body the securing element can be engaged in, say, the two pieces of fabric which, when the inner body is moved axially inwardly, are trapped between the securing element and the outer body.