An astragal is commonly used to seal between a pair of doors. The astragal closes the clearance gap. The vertical member (molding) attaches to a stile on one of a pair of doors (either sliding or swinging) against which the other door strikes, or closes. Exterior astragals are kerfed for weatherstripping. Also flush head and foot bolt hardware is commonly mortised into the astragal to hold the inactive door in place, when both doors operate, at the top and bottom.