A boom, in the context of windsurfing, is a piece of equipment that attaches to the mast, providing structural support for the sail. Early booms were tied on to the mast, using rope, but most newer booms use a clamp mechanism for attachment. Booms are commonly made from aluminum, or carbon fibre, and are often referred to as a wishbone boom due to their symmetrical shape. Windsurfers use the boom to hold and maneuver the rig, either directly gripping it in their hands, or through the use of harness lines. The boom mast attachment; is the inhaul and the boom sail attachment (at the opposite end) is the outhaul.
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