Stillson wrench

 'Stillson'-wrench  The ‘Stillson’ wrench is designed so that when pressure is applied, all the stress is transmitted through the hooked jaw and adjusting nut to the handle jaw, without the frame bearing any significant load. All parts are forged from high quality steel and are heat treated to ensure maximum strength. The teeth on each jaw oppose one another to enable a ratcheting action to be applied as the nut loosens and frees off.