The curling broom, or brush, is used to sweep the ice surface in the path of the stone (see sweeping) and is also often used as a balancing aid during delivery of the stone. Modern curling brush handles are usually hollow tubes made of fibreglass or carbon fibre instead of a solid length of wooden dowel. These hollow tube handles are lighter and stronger than wooden handles, allowing faster sweeping and also enabling more downward force to be applied to the broom head with reduced shaft flex.