This replaces standard A2 style sight posts in any typical fixed or folding sight. The Blitzkrieg Components Spike Front Sight Post provides superior sighting with a sharp aiming point and a bold, fast sight picture. The sharp aiming point enables precise aiming and high confidence on difficult shots. The bold, contrasting Luminescent Green Stripe gives the shooter an eye catching sight picture that excels in both bright-light and low-light environments and against all types of backgrounds. It is very fast and very easy to see. The luminescent stripe is visible on one side only so that it doesn't glow toward the enemy. Precision machined from billet 416 Stainless Steel with a matte black finish for an outstanding sight picture and precise fit in front sight housing including standard A2 fixed front sights and popular brands like Troy, Diamondhead, Samson, MI, YHM, Daniel Defense and Magpul plastic MBUS Gen 2. Fits anything that accepts a standard A2 front sight post. The Luminescent Green Stripe appears more yellow in daylight and glows green in low light. This gives you a bright yellow contrast stripe in daylight and a bright green glowing stripe in low light and darkness. The luminescent glow can be charged in seconds in sunlight or with a flashlight. Glows brighter than tritium or fiber optic when in low light or darkness. Gradually fades in brightness after charged and can be quickly recharged. Simple Drop-In installation. Simply unscrew the factory sight post and screw in the Blitzkrieg Components sight post.