Zenith 400B

Calibre 400B is an automatic chronograph movement from Zenith. Released in the 1990's, this was one of the first modifications to the classic El Primero movement.

Because of the unconventional 4 30 date window placement in the classic El Primero movement (now known as Cal. 400), Zenith created a new calibre, Cal. 400B, which moved the date to the 6 00 position. This modification required much reengineering of the movement, resulting in a jump in component count from 278 to 328.

Cal. 400B was also produced in titanium.

• Zenith 400
• Zenith El Primero
• Zenith El Primero calibres
• Zenith El Primero watches