18" Insulated Aluminum Flexible HVAC Duct R-4.2 – 25' Length Color_R-4.2 Yellow while the ingenious dial-controlled damper

while the ingenious dial-controlled damper empowers you to effortlessly regulate airflow using your foot

+ Product Details Size - 8"w X 30"h is the size for the duct opening measurement only

this coil exceeds the required 700 PSI for R410 with a pressure rating of 2300 to 6500 PSI

If your hole is 14" wide by 20" tall

18" Insulated Aluminum Flexible HVAC Duct R-4.2 – 25' Length Color_R-4.2 Yellow while the ingenious dial-controlled damper+ Product Details High Quality Aluminum housing on the outside and on the inside for the best insulation value Insulation A thick blanket of fiberglass insulation provides you with an R Value of 4. 2 Energy Efficient Air tight inner core decreases the pressure loss and provides a more hygienic environment high energy efficient No fiberglass erosion into air stream Design Designed to withstand bends and sharp turns without kinking. Tough reinforced