Hamilton Thin-O-Matic Masterpiece - Micro-Rotor - Cal. 628 - Circa 1963-1965

Offered here is a beautiful Hamilton Thin-O-Matic Masterpiece, a slim automatic from the early 1960s built around one of the most elegant movement designs of the era. As automatic wristwatches got thicker in the postwar years, the micro-rotor was the unique solution: the winding rotor is integrated into the movement's profile instead of stacked on top, allowing the case to stay genuinely thin while still giving you a true automatic. Collectors often discover micro-rotors through the Universal Genève Polerouter, famous not just for the name, but for how breathtaking a well-designed and perlaged movement can look. Universal Genève Polerouters today command prices of $1,000 to $2,000.

This Hamilton is far less known than the Polerouter but it delivers a micro-rotor movement as beautiful as the Polerouter at a far more approachable price point.

This example is especially strong. The dial is clean and bright with a crisp silver sunburst finish, applied faceted markers, and a perfectly balanced 12, 3, 6, 9 layout that reads as pure mid-century restraint. The Thin-O-Matic signature is subtle and correct, and the warm suede strap complements the gold tone beautifully without making the watch feel overly dressy.

Inside is Hamilton's Cal. 628 micro-rotor automatic, presenting in excellent condition with a sharp, clean appearance throughout. The case is correctly signed Hamilton Watch Co., Lancaster, PA, and marked 10K gold-filled bezel with a stainless steel back, with period markings including shock resistance and lifetime mainspring.

Terms: Please review all photos carefully as they are a part of the listing. This is a vintage timepiece. Accuracy, power reserve, and water resistance are not guaranteed. Vintage watches may require periodic service. Performance can vary with wear, temperature, and position.

I am happy to service any unserviced watch listed on the site — please inquire about service charges when purchasing.

All sales final.