Hi,
Here is a kit which was part of a series of six vacu-formed kits from the French manufacturer Ventax of Paris and issued in December 1959/January 1960.
I show you the SO 9050 Trident II in about 1/100 scale.
I found five of those kits some years ago and built only this one. Decals were unusable...

The world's first vacu-formed kit...

The world's first vacu-formed kit...

The world's first vacu-formed kit...

The world's first vacu-formed kit...
The finished model :

The world's first vacu-formed kit...

The world's first vacu-formed kit...

The world's first vacu-formed kit...

The world's first vacu-formed kit...
Cheers,
Jicehem