Seat air supply outlet, also known as floor type swirl outlet, its air flow is swirling and sent out, with high induction rate, the temperature drops rapidly and the noise is small; it can be installed on the vertical surface of the ladder or the floor, without affecting the walking of the personnel. The stepped air supply outlet is composed of air supply panel, connecting pipe and sector gate, which has the characteristics of multi-directional air supply and adjustable air volume. It is mainly installed under the seats of the meeting room and gymnasium.