The 9100 round seat has a full 14” round top and is made up of a special combination of foam for stability and comfort. The 9101 is identical to the 9100M, but with an extra-low tripod base for low-seated players. Minimum Height: 17.5" [44 cm] Maximum Height: 25" [64 cm] ***This item may ship direct from the manufacturer. Please contact us for estimated delivery if needed.***