These sights were copied from the Sharps M1874/75 but will work on other guns of similar configuration. All sights are CNC machined from solid bar stock. Sight base mounting holes are 2 ¼” apart. Recommended for BPCS shooters. A card of 12 interchangeable front sight inserts is included with each globe front sight. All sights carry a lifetime warranty; damage from obvious abuse will be repaired at a modest charge. Registration of product purchase is required.