Your new range hood Windster RA-76 Series Extension Duct Cover needs to sit between 28- and 32-inches above the cooking surface for optimum performance. This duct cover extension kit provides a sturdy outer shell for ceilings between 9.5- and 11.5-feet in height. Thick, durable stainless steel is used in the making of this unit, featuring smooth edges and a seamless design made possible thanks to Windster's superior welding techniques. This duct cover is intended for use with Windster brand range hoods from the RA-76 series. The unit is certified by the CSA for use in both the US and Canada.