Promura was a budget lens brand marketed through mail-order and department-store photographic catalogues in the 1960s and 1970s, rebadging Japanese-made optics for buyers wanting affordable telephoto reach on their SLRs. The 135mm f/3.5 was a typical catalogue-brand short telephoto of the period.
The lens uses a preset aperture design typical of the era, with a separate ring to set the working stop before shooting since it lacks automatic diaphragm coupling. It was produced primarily in M42 screw mount to suit the widely compatible Japanese and East German SLR bodies of the time.
Build quality reflects its budget positioning, with simpler multi-element construction than contemporary first-party telephotos and a modest level of coating compared to brand-name equivalents. Sharpness is usable stopped down but softer wide open than better-known 135mm primes of the period.
These lenses now surface occasionally at car-boot sales and secondhand camera stalls rather than specialist dealers, usually priced as low-cost curiosities. Buyers should check the preset ring turns smoothly through its full range and that the aperture blades are free of oil, a common issue on lenses of this age.