Because of their versatility, traditional round seats are still in demand. TAMA's own Round Rider seat features a 90mm thick, 13" diameter round seat. 1st Chair's famous base section offers both fast adjustments and great stability. The HT430 model features the Trio tripod. The HT440 Quartet 4-leg version is also perfect for keyboardists. Adjustable Height Range : 470mm-680mm (18 1/2" - 26 3/4")