The Valjoux 7750 movement was extremely important to the resurgence of IWC and the basic design remains in use today. The company has used it for many important innovations since the 1980's, including a perpetual calendar, rattrapante, and grande complication. The 7750 ebauche was used for the 790 family of movements and the basic architecture is the basis for today's 69000 family of movements.
In 1985, IWC surprised the world with the introduction of an innovative perpetual calendar movement, Cal. 7906. Designed by the legendary Kurt Klaus, this movement was much simpler to operate than previous perpetual calendars and was reliable and relatively affordable as well. A minute repeater variant, Cal. 79091 was introduced in 1991 for the Grande Complication, Ref. 3770. In 1993, IWC's Richard Habring created a rattrapante complication for the 7750 base, Cal. 79030. Two years later, on the 10th anniversary of the original Klaus perpetual calendar, these complications were combined in one movement, this Cal. 79251.
Cal. 79251 began with a Valjoux 7750 ebauche before being disassembled and modified by IWC. The movement was refinished and plated with gold, then assembled and regulated by the company. It was used in the Da Vinci Perpetual Rattrapante, Ref. 3751 from 1995 through 2001.
- 79252 (2001-2005) - Modified setting lever
- IWC Da Vinci Perpetual Calendar Rattrapante 3751 (1995-2001)
- IWC Da Vinci Perpetual Calendar Rattrapante 3754 (2001-2005)
- Bi-directional winding