This is an original vintage 1950s men's watch case complete with its screw-down case back. It is a genuine part from a Swiss-French automatic watch, originally housing the legendary Felsa 690 Bidynator movement. The inside of the case back is stamped with Monertus Trad Co / France. The exterior of the stainless steel back features vintage specification engravings including Incabloc, Automatic, Antimagnetic, and Waterresistant, along with the serial number 30310. The sale includes the brass case, the original acrylic crystal, the stainless steel screw-down back, and two vintage spring bars. This item is perfect for watch restoration projects, custom brass watch builds, or as a donor for rare vintage parts.

Condition
The item is sold in as-is vintage condition for parts or restoration. The brass case was originally gold-plated, but there is severe gold plating loss and heavy wear throughout from decades of use. The metal surfaces show scratches, scuffs, and a natural aged patina. The original acrylic crystal is intact but shows significant vintage scratches and will require polishing or replacement. The case has never been modernly polished or reshaped, fully preserving its original lines, geometry, and lug profile. The threads on the screw-down stainless steel back are in good working order. Please review all high-resolution photos carefully to evaluate the cosmetic condition before purchasing.

Specifications
Brand on case back: Monertus Trad Co
Country of origin: France
Estimated production era: 1950s
Compatible movement: Felsa 690 Bidynator and related calibers
Case material: Base metal brass (originally gold-plated)
Case back material: Stainless steel
Case back type: Screw-down
Serial number: 30310
Inclusions: Case, screw-down back, acrylic crystal, spring bars