What is the iDO? It is a mast base that limits the lean of the sail, designed for boards 85cm wide or more, and with sails up to 5m2. What does the iDO do? It eliminates the need to uphaul and the need to balance the sail for beginners. What difference does it make? People can windsurf instantly.And we really do mean instantly. The difference it makes is equivalent to trainer wheels on bicycles. Without them, people need to learn to balance on two wheels before they can ride a bicycle. With trainer wheels, they can ride instantly, and as they pick up speed, they naturally start to balance on two wheels as normal.With its angle limitation,everyone can windsurf instantly too,moving forward and maneuvering the board with natural feel and without fear of falling.