J shaped rail design reaches around irregular shaped objects. Ideal for holding I-beams during welding. Replaceable Perma-Pads for use of V-groove, serrated, or plain pad accessories. Spark-Duty copper-plated spindle extends the life of the clamp by protecting the spindle and pad from harmful welding spatter. Increased throat depth provides a deeper reach for unique projects. Quick-Twist Pads are simple and fast to replace with a V-Groove pad included in every box, or optional serrated pad. Ergonomic Wilton-Grip® has anti-fatigue properties and provides comfort during repetitive clamping. Drop forged arm provides minimal flex under heavy work loads.