ISA Swiss 8172

Quartz chronograph of the historical ISA Swiss range, documented as 8172/220 and also called 8172A. It has small running seconds, a central chronograph seconds hand, a 30-minute counter, pointer day and date. The official sheet specifies automatic stop/reset after two hours of timing and a chronograph seconds hand advancing five steps per second. Attribution is to the historical ISA quartz range, not a claim of manufacture by the current ISA Timepieces Swiss SA mechanical-movement company.