The Alder Force is a truly affordable way to get you hooked! The Alder Force board is lightweight and manoeuvrable, with a crescent tail design so you have greater control and a hard slick bottom for speed!* Lightweight and manoeuvrable* Controlled crescent tail design* Hard slick bottom for speed* Wrist leash included We say: 39" is the middle size in this range and popular with kids over 10 and small adults. Smaller children can go for a 36" and most adults choose the 42" (bigger men may want to consider a 45" heavier board).