Decocking Lever

On a double-action/single-action semi-automatic pistol, a decocking lever allows the cocked hammer to be lowered safely until the sear engages a safety intercept notch that prevents the gun from firing. This does not require pressing the trigger and defeating the other mechanical safeties in the pistol. The decocking lever is used to safely take a firearm out of a single-action firing condition when a round is still chambered.