IOR is the acronym for the name of Întreprinderea Optică Română (Romanian Optical Enterprise). It is a major optics company established in 1936 in Bucharest, Romania. I.O.R. produces military and civilian grade optics for export and domestic production. Famous for its own version of the Russian PSO-1 type scopes (LPS 4x6° TIP2), binoculars and other optics. Originally created by Malaxa-Carp, Optique De Le Vollois, and Bernard-Turnne, I.O.R. continued production under Soviet domination yet maintained links to famous Western European firms such as Carl Zeiss and Leica. These firms assisted I.O.R. in its modernization and expansion in the 1970s. I.O.R. is still in existence today and produces both military and civilian grade optics that are exported throughout the world.
I.O.R. optics are currently imported into the US by Valdada Optics and are marketed as "IOR Valdada".
I.O.R.'s LPS 4x6° TIP2 scopes are commonly found on Eastern Bloc sniper rifles such as the Puşca Semiautomată cu Lunetă, and SVD Dragunov. It is also a very common optic on the US commercial market on rifles that feature a compatible side rail mount. I.O.R. was one of the Cold War era manufacturers that survived the transition to a non communist era rather well. This was due in no small part to their close associations with Western European manufacturers and their 1970s modernization. Other manufacturers like the Russian Novosibirsk Instrument Making Plant and Belorussian Zenit company have not been as successful in entering the Western market.
Guns Magazine, Sept, 2003 by David M. Fortier; "SOF Field Tests Tactical Optics From Romania" By David M. Fortier January and February Soldier of Fortune 2003.