Nighthawk Custom Heinie Ledge Black Rear Sight Novak Cut .125 EZ Lock. 125 rear notch width. The rear face of the sight is serrated and a smooth front leading up to the ledge clear of any snag points for easy carry. The serrations on the rear of the sight eliminate glare from light sources while aiming. The Ledge rear sight is designed to help shooters rack the slide with a single hand. This rear sight requires machining of the slide for installation. Heinie recommends having a competent pistolsmith install these sights. Some fitting may be required Specifications for Nighthawk Custom Heinie Ledge Black Rear Sight: Manufacturer: Nighthawk Custom Color: Black Rear Blade Height: 0.325 in Mount Type: Dovetail Package Contents: Nighthawk Custom Heinie Ledge Black Rear Sight Nighthawk Custom SI0042-EZ: Heinie Ledge Black Rear Sight Novak Cut .125 EZ Lock