TROPEN Summar 2/5cm *

special Summar lens (Leitz product number 42214) designed for tropical conditions, very rare variant of the regular Summar (product number 42134) with an extra element at the front of the lens (optical formula B246a), which makes it a seven element construction, Leitz factory records indicate 'TROPEN' for these very few lenses, which are to be found among the late Summar lenses shortly before the introduction of the Summitar, the only difference visible from the outside is the groove along the collapsing barrel - same as in the Summitars, the offered lens is one of very few known to exist, see the James L. Lager article in Vidom no.85