4' Galvanized Rectangular Duct SKU 1414D4 Please select 13 3/4" SQ DUCT 4' LTHS PCS.14 1/2 X 20 DUCT 8' LTHS PCS15 3/4" SQ DUCT 4' LTHS PCS16.5 X 20 DUCT 4' LTHS PCS17 3/4" SQ DUCT 4' LTHS PCS19 3/4" SQ DUCT 4' LTHS PCS24" x 20" 4' DUCT Log in to view price