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. Our patented, injection molded sleeve design not only holds our tritium vials securely in place, it creates a brighter and more durable ring, we call The Perfect Dot, that provides maximum visibility both day and night. The domed lens collimates tritium rays for a sharper sight picture. CNC Machined out of high quality steel. Black Nitride coating used to improve wear and corrosion resistance. Gunsmith recommended for installation. Built in the USA with Swiss Tritium. Front Sight Width: 0.140″. Front Sight Height: 0.213″. Rear Sight Height: 0.256″. Compatible w/Glock 17/17MOS/19/19MOS/22/23/26/27/33/34/35/37/38/39/42/43/43X/45/47/48.