Introducing the XS Sight Systems DXW2 Pre-Drilled Front Night Sight for Smith & Wesson 586, 686, 625. The XS DXW2 Night Sights are purpose-built to give your Smith & Wesson revolver modern visibility, rugged precision, and 24/7 confidence. Whether you're carrying for personal defense, exploring dangerous back country, or just want tighter groups at the range, this sight is the upgrade your wheel gun deserves. At the core of the sight system is a tritium powered front sight. It is surrounded by our EMBER technology, a photoluminescent glow dot for maximum contrast in low light and bright conditions. FeaturesTritium powered front sight Big Dot front measures 0.188"Standard Dot front measures 0.140"High-contrast colored front sight Glow dot absorbs ambient light and glows in low lightDurable CNC machined steel 12 year warranty on tritiumKit Includes: front sight, windage nut, windage screw, red threadlocker, insert with instructions