Steambow AR-Series - Carbon Heavy Warbolts Set of 5 pcs. Black. They have a high-quality aluminum nock and a hybrid carbon/aluminum shaft meaning there is an aluminum core running inside the carbon shaft. This complex structure offers outstanding flight characteristics and makes the arrows extremely robust. At a weight of 247 grains these arrows are considerably heavier and strike their target with high momentum. This allows them to carry extreme momentum into the target and to transfer a high degree of energy from the limb. This momentum combined with the sharp blade makes these arrows very effective and extremely dangerous. Specifications for Steambow AR-Series Heavy Warbolts: Manufacturer: Steambow Color: Black Package Contents: Steambow AR-Series Heavy Warbolts Steambow 643: AR-Series Heavy Warbolts Black