The fastener includes a backing and rows of rail segments and rows of posts protruding perpendicularly from the backing. The rows of rail segments and rows of posts alternate. Each of the rail segments has a base portion attached to the backing and a cap portion distal from the backing. The cap portion has a cap width that is greater than a width of the base portion, and the cap portion overhangs the base portion on opposing sides. The base portion has a length that is greater than the width of the base portion. Each of the posts has a height that is no greater than a height of the rail segments and a length that is different from the length of the rail segments. A fastening system that includes the fastener and a package that includes the fastener are also described.