Model 350 is designed to accommodate installations that require a shallower stud bay or additional space behind the Dryerbox. This model's depth from the nailing flange to the rear is 3 1/2" and will fit in a 2 X 4 stud bay. It is important to note that Snaplock pipe becomes "ovalized" when drywall is secured to the studs. To handle this compressed stated, model 350s have an oval port. This makes attaching transition hose a little more challenging but is a compromise to support unusual requirements.
For standard installations, 2 X 6 studs or 2 X 4 studs with 1" furring strips are recommended to provide enough room for model 480 or model 425.