When it comes to tritium gun sights, aluminum sleeves and painted-on white rings are the norm. Night Fision breaks the mold, literally. Their patented, injection molded sleeve design not only holds the tritium vials securely in place, it creates a brighter and more durable ring, they call The Perfect Dot(TM), that provides maximum visibility both day and night. Features: a Perfect Dot(TM) Night Sights with added daytime florescent or phosphorescent ring a New, Updated Serrated Sight Body a Brightest Tritium Night Sights on the market a CNC Machined out of high quality steel a Black Nitride coating used to improve wear and corrosion resistance a Installation: Gunsmith Recommended a Built in the USA with Swiss Tritium a Fits Glock 42, 43, 43X