The Master Flow 10 in. x 6 in. x 6 in. 90 Deg Register Box is made of galvanized steel. It creates a right-angle transition from round pipe or insulated flexible duct to an air register or grille. This register box can be installed using sheet metal screws. It is suitable for most HVAC applications.Made of galvanized steelCreates a right-angle transition from 6 in. round pipe or insulated flexible duct to a 10 in. x 6 in. air register or grilleCan be installed with sheet metal screws not includedAlways seal seams with code-approved mastic, sealant or duct tape not includedAlways insulate ductwork for greater system efficiency and comfort insulation not included