Tekton breaker bars have heads that pivot smoothly and continuously through a 230-degree arc. An internal spring controls the tension of the head, allowing it to hold its position while you work. The head is made of AISI 4140 steel and heated to be stronger and more ductile than the handle. Our external head design resists spreading, twisting, or fracturing better than an internal head design. Tekton breaker bars exceed industry standards for Proof Torque, a measure of strength verified by a single-cycle test that applies torque until the specified value is reached without failure or permanent deformation. These breaker bars have a sleek, comfortable handle with a finger groove that has pronounced interior edges for traction and control for any finger placement. The pommel at the end of the handle keeps your hand from slipping off and is rounded for comfort.