The S21 was the first Supreme to introduce the Quickfill Ballast system which is a 1000lb hull-flooding ballast that fills the liner with water in under a minute. Optional Plug &amp; Play ballast is available for professional wakeboarding and wake surfing. Inspired by the S226 the S21 is a wake surfing machine. The largest boat in its class with is excessive freeboard for performance, safety and spacious seating you&#8217;ll be shocked at how big this smaller boat is. A larger extreme pickle-fork design gives maximum seating for 12.