Night Fision's patented, injection molded sleeve design holds their tritium vials securely in place using ballistic materials. Night Fision night sights carry more tritium than the average night sight on the market and a domed lens engineered to create the a crisp, defined glow.Features:a Brightest Tritium Night Sights on the marketa Domed lens collimates tritium rays for a sharper sight picturea Serrated for low-glarea CNC Machined out of high quality steela Black Nitride coating used to improve wear and corrosion resistancea Installation: Gunsmith Recommendeda Built in the USA with Swiss Tritium