This International Standard specifies the types and fitting dimensions of mechanical and electromechanical watch-movements.
This International Standard is applicable to the four following types of movements:
— Type 1: round;
— Type 2: shaped round;
— Type 3: 5 1/2'''
— Type 4: 6 3/4 × 8'''.
BS ISO 3764:2000 history
2016BS ISO 3764:2016 Timekeeping instruments. Movements. Types, dimensions and nomenclature
2001BS ISO 3764:2000 Timekeeping instruments - Movements - Forms, dimensions and nomenclature
1998BS ISO 3764:1998 Timekeeping instruments. Movements. Forms, dimensions and nomenclature