The Star M-07 mainsail is a more downrange sail but goes up to 15 knots nicely. The body is manufactured from a 3.6oz Dacron with a radial head and clew. This sail is developed to provide maximum power and get the crew over the side very low down in the wind range. The M-07 mainsail fits all the new masts nicely and is a great sail to have if you race primarily in lighter wind conditions.