Soligor — 300mm f/5.5 manual preset telephoto prime, multi-mount fit for vintage SLRs
The Soligor 300mm f/5.5 was a catalogue telephoto prime from Allied Impex's Soligor brand, widely sold during the 1960s and 1970s as an affordable long lens for SLR owners unwilling to pay first-party telephoto prices. It sat within a broad telephoto lineup spanning 135mm short teles to 500mm mirror lenses.
Like most Soligor primes it was supplied in a range of interchangeable camera-mount fittings rather than one fixed mount, so the same lens body could be bought to suit whichever SLR system a customer owned. Diaphragm control on 300mm-class lenses of this era was frequently a preset ring rather than automatic, and focusing is entirely manual via a long helicoid throw.
Wide-open performance is soft by modern standards, needing to be stopped down two or more stops for acceptable contrast and resolution, with muted colour compared with later multi-coated designs. The slow f/5.5 aperture limits use in low light.
Secondhand examples are common and inexpensive, frequently listed without caps, cases or hoods. Check that the preset aperture ring clicks correctly at each stop, the focus helicoid moves smoothly, and the mount is the exact fitting required.