Abstract: A stowable seat back tray table for pivotal support on a pair of support arms pivotally attached to a seat back comprises a first tray table section having upper and lower parallel planar surfaces pivotally attached to a pair of support arms for pivoting between a generally vertical stowed position and a horizontal operative position, second generally rectangular planar panel member slideably mounted on the first member and having a planar support surface selectably positionable to a stowed position overlying the first support surface and an operative position providing an extension of the first support surface, and an extensible drink container well formed in the first panel member and having a vertically extensible container support member extending below the support surface for selectively extending the depth of the well.