Abstract: A fastener comprising a longitudinally extending member having a hub region and at least two arms extending in a longitudinal direction from the hub region, the member defining a plane and having a length and a width less than the length, the arms each being provided with a sharp edge, the hub region being provided with an engaging member for receiving a rotational force about an axis perpendicular to the plane of the member for rotating the member in the plane of the member, the fastener adapted to be inserted in a longitudinally extending groove in an object to which the fastener is to be secured, the groove being at least coextensive with the length of the longitudinally extending member and having a width at least as large as the width of the member, the fastener being adapted to be rotated via the rotational force once inserted in the groove so that the sharp edges of the arms cut into sides of the grooves thereby forming undercuts securing the fastener in the object.