Each pack contains one 40″ piece of 0.015″ diameter Ultra Super Flex fiber in brilliant blue. USF fiber is our standard bright fiber, which is excellent for general use in a variety of aiming applications. USF flares easily with heat (if needed), allowing for installation in nearly all sights styles.

Please note: Blue fibers rely on UV light to produce maximum brightness. This can be achieved by using the fiber outdoors, even in overcast conditions. Additionally, a UV sight light may also be used. Blue fibers may appear dull indoors where UV light is minimal.

Visit our products page to view additional sizes and colors.