CAMP DRYAD PRO SMALL DOUBLE MOBILE PULLEY. Compact double pulley for block-and-tackle systems. Large connection hole accommodates two carabiners. For ropes up to 13 mm. Prusik minding, the self-locking knot can be installed on both sides and both wheels. Sealed ball bearings for high efficiency and intensive use at high speed. Efficiency: 80%. Aluminum alloy body and wheels, stainless steel axle.