The TRUGLO Long Beard front sight is a universal fit turkey front sight for vent rib barrels. Simply remove the existing front bead and select the proper screw size by using the chart on package or by matching the removed bead. If the original bead is pressed into rib, the hole can be easily tapped. The Red or Green sight simply screws onto the new threads. Note, if necessary use a small amount of thread locker. The fiber optic is protected in the sight base but still collects an ample amount of light. The fiber is .060" in diameter.