San Giorgio collimatore
Early reflector Gunsight with a very small optical system and aperture. Used on light artillery guns but also some aircraft turrets and flexible gunnery positions on Italian bombers.
Most often described on internet as the Tipo A which it certainly is not and also as a fixed gun (i.e. fighter) Gunsight which it most probably wasn’t either. Confusion comes from the AF museum in the US which used one of those in the restoration of their Macchi M.C. 200 Saetta. This is most certainly one of the too many unfortunate case where a museum used what they had in their collection to “fill a hole” instead of sourcing the correct equipment or leaving it empty while searching for the correct instrument.
Collimatore a reflessione per velivoli da cacia
San Giorgio Tipo A
First of a series of reflector Gunsights developed and produced by San Giorgio, the Tipo A (type A) entered service in 1937 but apparently only saw limited use, mostly in some early Fiat G.50 and Macchi Mc.200. It was originally fitted with a two circles and three dots (within the small circle) reticle later changed to a two circles with only center dot reticle.
Even though obsolete by war end, it was still mentioned in a 1946 Italian manual on sighting devices.
San Giorgio Tipo B
San Giorgio Tipo C