(800)865-5931 Closed Thur 11/26 - Sun 11/29, Reopen Mon 11/30 8am, CT
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The Alpine SBD30-100-244 has been discontinued.
Please call us for a suitable alternate product.

(800) 865-5931

Closed Thur 11/26 - Sun 11/29, Reopen Mon 11/30 8am, CT

This return air support box and plenum kit is for use with systems where the return air must come in underneath the furnace or air handler. The kit includes 8 feet of 24 inch by 8 inch sheet metal ductwork that can be custom trimmed to the correct height for most applications, and a support box that can hold a furnace or air handler up to 22 inches wide. The support box features an interior support bracket for maximum strength, and a 20 by 25 inch filter slot that can accommodate a one, four, or five inch thick media filter. This kit does not include a filter. Please  click here to see our recommended filter. For return air box only, please see the Snappy SBD30 .

Filter Size
20 x 25 Inches
Support Box Dimensions
30W x 28D x 10H inches
Duct Size
8 x 24 inches
Use Media Filters of Thickness
1 / 4 / 5 inches
Duct Length
8 ft
Max Furnace or Air Handler Width
22 inches
10 Inches