... 10 c) (American Standard)Warringtonfire Test Report2. High Production Capacity:Tenglong handles an annual capacity of 120,000 door sets. which ... of door sets to defferent porjects.3. Competitive Price:Tenglong Fire Rated Doors are all designed and manufactured in China ... of the certified manufacturers sourcing the door cores from overseas. Tenglong developed its own core and put it into production, ...