XS Sight's tritium standard dot fits Colt Cobra, King Cobra, and Colt Viper revolvers. The front sight features a bright tritium vial and is paired with a photoluminescent glow dot. The high contrast sight picture will increase your sight acquisition speed and accuracy. Don't struggle to see your sights in low light. The dual illuminated front sight provides high contrast in bright light and the glows in low light. XS Sights are a superior upgrade over the factory brass sight. Tritium powered front sight Standard Dot front measures 0.140" High-contrast colored front sight Glow dot absorbs ambient light and glows in low light Durable CNC machined steel 12 year warranty on tritium Kit Includes: front sight, blue threadlocker, hex wrench for front sight set screw, insert with instructions