The GearWrench Slugging Wrench, 4-1/2", 12 Point Straight (82399) is manufactured from alloy steel with a black oxide coating for greater strength and durability to handle the torque necessary to loosen and tighten large fasteners. It is part of the new lineup of GearWrench wrenches which have a large striking surface for more efficient hammer contact allowing more force to be applied to the fasteners allowing the job to be completed more quickly. They are designed and manufactured to handle the toughest of jobs.