Just to make cleare the connection between the brands (and without any disappointment for the point
).
The base car is a Fiat 1100/103 D (1957 edition).
Siata was responsible for tuning the engine, increasing also the displacement to 1250 cc.
Zagato made the aluminum body (styled by Giovanni Michelotti).
Siata itself sold some of them under the name "Siata 1250 GT".
Zagato too sold some of them (with almost the same body, apart from minor details) under the name Fiat 1100 GTZ or Siata 1250 GTZ wether having them the regular or the tuned engine.