Dryerbox Model DB-350
Upward Venting, 2x4 Wall

Model 350 Dryerbox^® - 22 gauge metal deep drawn recessed dryer vent box with gas port, measures 3 1/2 inches deep from nailing flange. For 2x4 construction but has a very oval shaped port on top to accommodate the squished 4" Snaplock pipe.
 

• 22 gauge aluminized steel weighing 4.03 pounds each
• Top port measures 4 7/8" x 3 1/8" oval shape
• Distance from nailing flange to rear of box is 3 1/2"
• Overall measurements: 21" h x 12 1/2" w x 4 3/8" deep
• Inside measures 9 1/2" wide x 18 1/4" tall
• Can be installed upside-down for dryers on a pedestal or stacked

Additional Resources:

Dryerbox Model Specifications 
Dryerbox Installation Tips  
Dryer Venting Guidelines  
Dryer Venting FAQs