Watch Terminology Dictionary

This refers to a center second style where the fourth wheel is not in the center. Generally, it refers to a center second style where a wheel is attached to the third wheel. This is rare in current movements because it increases the thickness of the movement. Girard-Perregaux's Cal. 3000 series achieves indirect center seconds without increasing the thickness by stacking two third wheels. A center second style movement where the fourth wheel is in the center is called a direct center second.