This is a 20"x20" Sheet Metal return air plenum ***( not for filter)***. Made in America by hand from American made 26 Gauge Steel Galvanized Sheet Metal . There is a 3/4"  hem flange on one 20"x20" end Outside the plenum (around the flange) has dimensions about
22 x 22" and height 5". We will install a round, starting collar 14" in diameter (Please specify size needed).  From top to bottom the plenum is 5" long and the collar measures 4" in length.  We are a complete sheet metal shop. Our prices are fair and our quality is unmatched.

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