STARTER TRAC® with drip edge. Face return flange 1-1/4" (32 mm) with striations which provide a strong physical bond for the base coat and perforations for bonding of the base to the substrate. Extra wide 3" (76 mm) nailing flange has striations on inside face to aid bonding of foam board to nailing flange. Base shelf has weep holes 3" (76 mm) o.c. to allow migration of water from system.