The Marble Arms Glow 50-W Fiber Optic Front Sight provides enhanced target acquisition with bright green fiber optic illumination and durable steel construction.Marble Arms Glow 50-W Fiber Optic Front Sight.500 inch diameter for standard rifle installationsGreen fiber optic element for bright sight pictureSteel construction for durability and reliabilityDesigned for improved accuracy and target acquisitionIdeal for hunting target shooting and tactical applications where fast accurate sight alignment is critical in various lighting conditions.