The Goodman SQRPGH101-102 / SQRPGH103 is a Square to round transition used for Goodman package units. It attaches to the return and supply openings of the unit and converts the ducts to match your applications needs. The SQRPGH101-102 converts the ducts to Supply 16 and Return 16 inch while the SQRPGH103 converts the ducts to Supply 18 and Return 18 inches. The correct transition must be selected for its corresponding Goodman package unit. Goodman has become one of the largest manufacturers of residential and light commercial air conditioning, heating, and indoor air quality products and systems by focusing on just one thing, building the most reliable and refreshingly affordable indoor comfort products in the market.