This sight set is for Glock pistols and does not require modifications to the slide. It is a Heinie LEDGE All Black design with a .156" wide and .120" deep notch. This sight design is great for one-handed clearance drills. FeaturesDesigned for easy one-hand cyclesQWIK notch width of .156"Notch Depth: .120"Front & rear sight serrations help eliminate light glareDurable Melonite finish DISCLAIMER: This product is not manufactured, authorized, endorsed, or warranted by GLOCK. GLOCK does not warrant or represent that this product is compatible with GLOCK pistols.