STANLEY 91-316, 3/4″ DRIVE ROUND HEAD QUICK-RELEASE RATCHET STANLEY RATCHETS AND ACCESSORIES ARE DESIGNED TO MEET OR EXCEED ANSI SPECIFICATIONS. FORGED FROM HIGH-QUALITY STEEL AND FINISHED IN HIGH-POLISH CHROME. SELECTED STANLEY HIGH-TORQUE RATCHETS HAVE A QUICK RELEASE MECHANISM FOR ONE-HANDED USE. SOCKETS AND EXTENSIONS REMAIN LOCKED ONTO THE DRIVE UNTIL DISENGAGED WITH AN EASY-TO-REACH, LOW-PROFILE QUICK-RELEASE BUTTON. RATCHET HANDLES ARE ERGONOMICALLY DESIGNED. RATCHETS HAVE AN EASY-TO-USE, THUMB-OPERATED REVERSE-SWITCH MECHANISM.