bottom of the boom, and to secure the reef points to the fore and aft of the boom. With a well designed system sailors can reef the sails without leaving the cockpit. Other lines that may be found on a boom include: A topping lift, holds up the free end of the boom when the sail is lowered. Lazy jacks guide the sail onto the top of the boom for furling when the sail is lowered. Boom material and hardware Traditionally booms, and other spars, were made of wood. Classic wooden hulled sailboats, both old and new, will usually have wooden spars. When aluminium became available, it was adopted for sailboat spars. Aluminium spars are lighter and stronger than their wooden counterpart, require less maintenance and generally hold up better to marine conditions. Aluminium spars are usually associated with fibreglass boats, although one can still find a few early fibreglass hulled yachts that were equipped with wooden spars. On very large sailing vessels, the spars may be steel. Modern, high performance, racing yachts may have spars constructed of more expensive materials, such as carbon fibre. Various hardware is found attached to the boom. The hardware could include fairleads, blocks, block tracks, and cleats. For attachment, screws are used on wooden booms and screws or rivets on aluminium booms. If the foot of the sail is attached to the boom, there may be hoops from the foot of the sail, around the boom, or there may be a track on the top of the boom into which fittings on the foot of the sail are slid. In-boom furling There are quite a few variations of in-boom furling available. Generally the boom is hollow with a spindle in the center upon which the sail is rolled (furled). The techniques for turning the spindle vary, but frequently a line is used to spin the spindle and recover or reef the sail. In most cases the sail can be full battened and has virtually infinite reefing options. Some sailors consider this approach safer than in-mast furling, since the sail can be lowered and flaked in the traditional method, in the case of mechanical failure. In most applications, the sail can be lowered or reefed from the cockpit. Most designs will not accommodate a loose-footed mainsail. Boom safety concerns The second leading cause of death on sailboats is directly attributed to the use of booms.