Things You'll Need
Instructions
Make sure your Glock 23 is unloaded and lock the slide in the rear position.
Press out the sight retention pin (which replaced the trigger housing pin when you installed the laser) from the right hand side.
Pull the sight off the back of the grip and remove the batteries from the interior of the sight (they are located, one each, on the flaps that go on the sides of the grip).
Replace the batteries with the positive sides facing toward the grip of the pistol (as you visually inspect them, you should be looking at the positive). Make sure the batteries are placed securely in position and test the batteries by pointing the laser in a safe direction and pressing the activation key on the back of the sight.
Place the sight back on the pistol and reinstall the retention pin.