Tekton curved jaw pliers have a curved section that locks onto hex-shaped bolts, rounded-off nuts, pipes, and square tubing with the aggressive bite of deep, sharp teeth. Easily set, release, and reposition the clamp with one hand and with more control than a traditional pinch-style lever. Get extra leverage and fine-tune your clamping force by inserting a screwdriver or hex key into the through-hole to create a T-handle. The jaws are made from 4140 chromium molybdenum steel, an alloy that offers toughness, machinability, and corrosion resistance. The teeth are hardened to 45-50 HRC and should not chip or strip even on fasteners up to Grade 8 or Class 12.9. The pliers have a durable, nickel-plated finish that protects against corrosion.