The 10-8 Performance rear sight is precision CNC machined from heat treated 4140 bar stock to better resist the nicking and denting that is typical with the wear and tear of daily carry. All 10-8 sights feature a U notch for rapid, intuitive alignment. The rear face is serrated at 40 LPI to reduce glare in varied lighting conditions. Plain black blade, finished in matte black oxide. The Kimber sight set features a .360" tall rear sight with a .125" deep X.135" wide U notch which is compatible with all Kimber fixed sight pistols with the forward slanting serrated rear sights. The front sight is .125" wide X .200" tall, also with 40 LPI serrated face. NOT compatible with the SIS family pistols.