|Complications:||Chronograph, Monopusher Chronograph|
|Hands:||30 Minute Chronograph Hand at 3:00, Central 60 Second Chronograph Hand|
|Distinguishing Technical Characteristics|
Counter-Clockwise Balance Cock
Cal. JB2 (and the similar Cal. JB20, JB22, and JB222) was a mass-produced stopwatch movement from Excelsior Park (Jeanneret-Brehm). It was produced in both standard and rattrapante versions and was available with 1/5 or 1/10 second timing. The latter typically featured a 30 second dial. Cal. JB2 was also available in either “815” or “990” versions, with the latter placing the 30 second counter further from the center (9.9 mm rather than 8.15 mm) for use in larger watches.
Cal. JB2 was the same size as the Roskopf Cal. JB3 and JB30 and the “first quality” Cal. JB1, with many watches available with a variety of movement grades. The standard size was 18 ligne, though it was also listed at 19 ligne.Images are taken from official publications and are used here for commentary and educational purposes. Copyright is held by the original owner as noted.