Single Piece Plenum

An air distribution system that includes a plenum, which has a bottom wall, a peripheral wall connected to the bottom wall and extending around a periphery of the plenum to define one or more open spaces in the plenum, and one or more connection recesses in the bottom wall adapted to connect to a blower. A top surface of the peripheral wall is configured to contact a bottom surface of a cushion of a vehicle seat to enclose the one or more open spaces.