These IRWIN® VISE-GRIP Original 7CR 7-inch Curved-Jaw Locking Pliers have a self-energizing lower jaw to provide more gripping power with no slipping or stripping. IRWIN® pliers provide maximum torque without requiring heavy input pressure, utilizing a jaw mechanism that naturally grips tighter as more torque is applied to the tool. A classic trigger release provides maximum locking force, and a curved jaw puts tremendous pressure on 4 points of most nuts and bolt heads, making the curved-jaw locking pliers perfect for maximum-torque applications.