Double-braced tripod base ;Fulcrum shaft height adjustment;With Memory Lock for height adjustment ;For thrones of the Gibraltar 9608 model series;Also suitable for other seats with 7/8" (2.22 cm) tube mount;Single braced tripod base;Fulcrum shaft height adjustment;With Memory Lock for height adjustment;Fits seats with 7/8" (2,22 cm) tube mount;Height adjustable approx. 51 - 71 cm;