All clips-on s have an internal cross hair,more than one design,several.Theres quiet a big menu to get thru,its there tho.So it can be zeroed with yr day scope cross.But i dont bother with that,just use day scope cross,simple.More important to have a neat tightish fitting attachment slide on to yr scope bell which centralises yr clip on view to yr day scope.Make sure both clip on and day scope have a similar fov on low x mag.
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