The strap adapter converts the strap hooks on the back of a 3D printed protective face shield frame to slots. The hooks were originally designed to be used with an elastic strap with slits (i.e. “buttonhole” elastic). The adapter allows the tourniquet strap to be attached and adjusted to a comfortable size for each user without cutting slits in the strap. An existing strap with slits can also be used with the adapter and adjusted for comfort.