HiViz red fiber optic front sight. Improves visibility in most lighting conditions and allows faster target acquisition. Base is CNC machined from steel and the fiber optic rod is protected by an over molded shield. Fits all Glock models. Dot diameter .125 = 1/8th inch. ________________________ That's Lone Wolf's description. Where I ordered it. I upgraded with night sights now. So this can go. Asking $20 shipped.