Costa Ludus sights include a proprietary Night Fision Perfect Dot(R) in the front sight and a horizontal tritium bar in the rear sight, for a unique and unmistakable sight picture. Serrated for low-glare, their shorter height stays well out of the way of your dot for a minimal co-witness. Our patented injection molded sleeve design holds our 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:Brightest Tritium Night Sights on the marketDomed lens collimates tritium rays for a sharper sight pictureCNC Machined out of high quality steelBlack Nitride coating used to improve wear and corrosion resistanceInstallation: Gunsmith RecommendedBuilt in the USA with Swiss TritiumFits Glock Models 42, 43, 43X