This Long Range Soule with 3.5" of elevation with long base for mounting on tangs with hole spacings from 1.78"-2.3". Elevation marked in .010" increments and windage adjustable to .001". Comes with two 10-28 screws, you must order seperately other screws if these will not work. These sights have the Old Style lead screw elevation adjustment with elevation markings on the left side of the staff only. Features 27 minutes of windage each side of zero.