The thick and oddly shaped 39mm case can be explained by another factor: the Beta-21 caliber that it houses, the very first Swiss quartz movement. Its chunky case with integrated bracelet is definitely reminiscent of its introduction in 1970 for a short two-year production. This reference 5100 does not look like your usual Rolex, either inside or out.

Lastly, the large winding crown is original to the watch, and completes the look of what was engineered as a true tool watch.

The dial shows some light aging towards its center, but the painted numerals remain intact and are very pleasantly balanced with the 3 sub-registers, which are well sized for the 35mm diameter of the case. The Borgel case is astoundingly sharp, the lugs have kept their original shape, and the 5866 serial number is deeply engraved (and matches the numbers on the caseback, as it should). The chronograph here does not feature the characteristic ' snake hands' usually found on the M95 chronograph, but the red handset is also correct for this reference. The highlights don't stop with the movement, since the waterproof cases of those chronographs were manufactured by the famous supplier Francois Borgel (later Taubert Frères), also known for its contribution to the first water-resistant Patek Philippe chronograph, the reference 1463. This is the exact opposite of how a chronograph wristwatch usually works, so it takes some time to get used to it, but it does not feel less efficient in the long run. In that regard, its calibers M90 (two-register) and M95 (three-register) offered an interesting peculiarity : the bottom pusher starting and stopping the complication, while the reset pusher is placed up top. Movado was at one time renowned for its in-house calibers, chronograph movements included.

Movado watch serial numbers