Overview Model # MFX48ULMK Store SKU # 1000718218 This All Metal Dryer Hook Up Kit is the ultimate installation kit for both the contractor and consumer. This kit includes one 4 in. x 4 ft. UL 2158A listed and marked semi-rigid aluminum duct, two pre-attached all metal heavy duty elbows and two 4 in. metal galvanized worm gear clamps. Semi-rigid duct is UL 2158A listed and marked for safe dryer venting and is thicker than the standard non UL semi-rigid version 2 metal elbows are flame resistant for a safe and long lasting connection New manufacturing technologies incorporated into the duct allows for easy rotation, adding durability during installation Elbows are designed to achieve tight 0 to 90 degree turns which saves space while still maximizing airflow and are crush resistant Show More