Hello eyepiece experts, I just added the 9MM UO Ortho(non HD) to my set of 5,7,12.5,18 and 25MM's. The 9MM is the only one that has additional lettering along the top. The unusual letters are
"O.P.S.". Can someone please clarify these letters? Thanks.
"O.P.S.". Can someone please clarify these letters? Thanks.