US Patent 7454802 Drain system for tub

An air massage bathtub is disclosed. The air massage bathtub includes a bath well defined by side walls and a bottom portion. The bottom portion includes a recessed area with a drain located within to the recessed area. The bathtub further includes a channel located at least partially below said bath well and in communication with the recessed area, and a plurality of apertures each of which extends through the bath well and into the channel.