Abstract: An adjustable roof curb system includes: a roof-mountable appliance; an adjustable roof curb device, including a top curb component with left and right pivoting pins and a base curb component; and locking screws; such that a longitudinal inclination angle is adjustable by pivoting of the top curb component relative to the base curb component; such that the adjustable roof curb device is adjustable for mounting on a pitched surface of a roof, such that the longitudinal inclination angle is equal to a roof pitch angle of the roof, such that the top surface of the top curb component is adjusted to be level; such that the roof-mountable appliance is level mountable on the top curb component.

Abstract: A flex duct fitting system includes: a flex duct with an inner lining, a flex duct fitting device, including a connector portion, including a connector portion body, a flex fitting assembly with a peripheral protrusion and a peripheral indentation; a circular fastener, such that the inner lining is pulled over the flex fitting assembly, such that the at least one circular fastener is positioned in the peripheral indentation and tightened around the connector portion body, with the inner lining tightened in place between the at least one circular fastener and the peripheral indentation.

Abstract: A flex duct fitting system includes: a flex duct with an inner lining, a flex duct fitting device, including a connector portion, including a connector portion body, a flex fitting assembly with a peripheral protrusion and a peripheral indentation; a circular fastener, such that the inner lining is pulled over the flex fitting assembly, such that the at least one circular fastener is positioned in the peripheral indentation and tightened around the connector portion body, with the inner lining tightened in place between the at least one circular fastener and the peripheral indentation.