A mechanical fastener is disclosed that includes a thermoplastic backing and multiple, upstanding fastening elements that have a post with a proximal end attached to the thermoplastic backing and a distal end comprising a cap larger in area than a cross-sectional area of the post. The basis weight of the mechanical fastener is in a range from 25 grams per square meter to 75 grams per square meter, and the height of the multiple, upstanding fastening elements is up to 300 micrometers. Fastening systems and disposable absorbent articles including the mechanical fastener are also disclosed.