Clamp-on steel extension adds a serrated lever to the side of the hammer spur to give your thumb a large, easy-to-find horizontal grasping surface. A must-have if using a low-mounted scope, heavy gloves, or you just want a hammer that’s easy to grasp under stress or in wet weather. Hollow design keeps weight to a minimum, so hammer speed and locktime are unaffected. Holds tight on left or right side of hammer with steel Allen head screw.