Pottorff is has introduced its new EXA-645 combination louver. The company says it is a high-performance louver with Best-In-Class AMCA certified performance for free area (50.4%) and a pressure loss of 0.15 in. wg. @1,272 fpm (6.46 m/s). The EXA-645 features stationary drainable louver blades that protect against water penetration along with an integral airfoil blade control damper which will allow for positive shutoff protection from air intake and exhaust openings. The EXA-645 has a durable frame system that channels water away from the louver and a drainable head that collects and removes water by cascading down the face of the building thus providing additional water penetration protection. Standard construction features blade and jamb seals that will provide a tight closure to minimize air leakage. The EXA-645 louver comes with a 5-year warranty.