This lightweight and compact throne has a 13 inch. round cushioned vinyl top, with top grade foam for maximum comfort. The base is single braced with a cast height adjust collar and nylon bushing. The height adjust support stem is knurled and allows you to fine tune your exact height. The knurled support stem is equipped with a memory lock that uses a wing nut tension adjustment. Features ·13 inch. vinyl, round throne top ·Single braced tripod base ·Compact and lightweight ·Cast height adjust collar with nylon bushing ·Knurled adjustable height stem ·Height adjust memory lock with wing