One Model 425 Dryerbox^® - 22 Ga. metal deep drawn recessed dryer vent box with gas port measures 4 1/4 inches deep from nailing flange. Mostly for 2x6 construction but will also fit into a 2x4 wall that has been firred out with one 1x2 firring strip. 

• 22 gauge aluminized steel weighing 4.14 pounds each
• Top port measures 4 1/8" with very slight oval shape
• Distance from nailing flange to rear of box is 4 1/4"
• Overall measurements: 21" h x 12 1/2" w x 5 1/8" deep
• Inside measures 9 1/2" wide x 18 1/4" tall
• Can be installed upside-down for dryers on a pedestal or stacked

Links: Drawings/Measurements  -  Instructions

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