Breathability - For the construction of this mesh office chair we use high density foam for the seat with a soft breathable mesh design. The high density foam increases air circulation preventing heat build up for much greater comfort during prolonged periods of sitting.Function Mechanism - For this enhanced size office chair we use a tilt lock mechanism to promote greater comfort when reclining. Support up to 250 pounds.Enhanced Size - One of the most common features that people comment upon is that a mid back chair doesn’t always offer the width and space needed to increase support and comfort.