The Ø 45 x 2.2 mm mast and Ø 27 x 1.5 mm sprit are made of the highest grade aluminium available. (7075 T6 Aerospace spec. alloy) and the super stiff BLACK GOLD mast and sprit can be used with a choice of booms : The 32 mm BLACKLITE boom A bendy boom, which comes with a bridle, will flatten and depower the sail which enables the lightweight sailor to go faster in more wind. The 40 mm BLACKGOLD boom A stiff and lightweight boom, which comes with a bridle and suitable for the majority of sailors. The 55 mm BLACKMAX boom The ultra stiff (and yet lightweight) boom can be used without a bridle. This enables the larger sailor to jump across the boat and not too far aft while tacking.