The Optiparts Silver Regatta Boom for the Optimist Sailing Dinghy. Designed as a Silver Regatta Boom, which has slightly more strength than your typical Optimist Boom. This lightweight 40 mm Silver Series Boom is much stiffer than the 32 mmSchool Boom and will allow the sailor to put more tension on the leech.SpecificationsColour: SilverLength: 40 mm