Used Springfield Man-O-War pedestal seat base with slide assembly. 22” overall height, 9” diameter base plate and 13” by 7 1/2” seat mounting surface with standard mounting holes plus (2) additional mounting holes have been added. This base will adjust fore and aft and will swivel but it is a fixed height assembly. There is some cosmetic corrosion and blemishes from normal usage however there is no damage and is fully functioning.