IRWIN QUICK-GRIP 223106 Medium-Duty Bar Clamp, 6 in Max Opening, 3-1/8 in D Throat              Clutch lock steel bar clamp with soft-grip handle is larger and more ergonomic, allowing high clamping pressure with less effort I-beam bar reduces flexing and bowing. Larger clutch plates allow for easier release and increase durability and dependability. Throat depth of 3-1/8 in.