A Harken Battcar system along with full-length battens helps raise. douse. and reef with ease and acts as extra crew if you’re sailing shorthanded. Battcar systems outperform in-mast or in-boom furling. cost less. and you don’t need to recut your sail. The one-piece solid aluminum construction is lightweight and strong. The free-rolling ball bearing cars let you hoist and reef the main quickly on all points of sail.