WSD-3639 provides a mechanical termite barrier and a means to deflect drainage water away from foundation surfaces in our WEEP System; it’s part of a technologically advanced design for creating division between the masonry and structural back-up walls. WSD-3639 consists of 26 gauge galvanized steel bent into a 120° “L” shape with a 3.453″ vertical attachment flange. WSD-3639 is used in conjunction with LR-3639 for ensuring durability, rigidity, and longevity.