Zenith is one of the most under rated watch companies out there especially their early models. The Sporto was already well advanced in design and the Caliber 40, a cheaper, more affordable option to the very famous Cal 135 but very well finished for its time. The watch is exceptional with little signs of wear, a previous watchmaker has scuffed the back but no other signs of mishandling seen on the watch. The special part of this model is the double "casebacks", one being the plexiglass dustcover, the second being the caseback itself hiding all the beauty of the movement.
Details:
 
Brand: Zenith
Model: Classic Sporto Case
Reference: ---
Year: 1960
Material: Stainless Steel
Dimensions:  37mm 
Crystal:  Plexiglass
Movement: Manual wind Cal 40
Bracelet/Strap: Wristwatchme Leather Band
Box/Papers: No/No