Phago's budget enlarging lens — the basic 50mm at minimum specification.
The Phago 50mm f/4.5 is a very basic enlarging lens from the obscure Phago brand. At 50mm f/4.5 for 35mm negatives. Phago is not a recognised optical manufacturer. The very slow f/4.5 provides dim focusing. Similar to the 150mm Phago enlarging lens described earlier — unknown origin, unknown quality, minimum specification throughout.
Quality unknown from the undocumented Phago brand. The f/4.5 is very slow — providing dim focusing in the darkroom. Basic flat-field correction at best. Not designed for camera use. The declining darkroom market makes even quality enlarging lenses nearly valueless — an unknown brand has absolutely no practical or collector value.
No camera mount. Enlarger thread. Unknown manufacturer with no documentation. Weight minimal. Build quality unknown. The most basic possible enlarging specification from an unrecognised manufacturer. No quality baseline can be established. Darkroom use only — and not recommended even for that.
No value whatsoever. Unknown brand. Very slow f/4.5. Better enlarging lenses available free from known manufacturers. Not a camera lens. Not recommended for any purpose whatsoever. Only if received completely free inside an enlarger that is itself essentially free.