Davis Instruments Black Max Wind Indicator Easy on-easy off Comes with clear plastic storage container Best for lasers or EL toros or sabots or and most small dinghies Attaches quickly to the mast or boom on most small boats such as Lasers and Sunfish Fits masts and boom ends from 1-1/2" to 2-1/2" diameter Tough high impact plastic vane, designed to withstand years of punishment and abuse Stainless steel mounting arm and set screw, as well as a tough plastic mounting base, add to the system's durability Wind vane length is 8"