XS Sights XS Standard Dot, Night Sights, Fits Colt Cobra, Green Dot CM-0015S-4G Standard Dot Night Sights are defensive tritium sights designed to enhance your carry revolver. The sights use a proprietary photoluminescent Glow Dot that absorbs ambient light and glows in low light. The convex dot's additional surface area increases light absorption" intensifying the charge of the Glow Dot. Designed to be large and highly visible" these sights help solve many issues" from aging eyes to deteriorating vision. We've found the green is an excellent option for low light and has a very bright glow intensity. XS Tritium Night sights are big" bright" and easy to see day or night!