IWC still used proven designs and ebauches for their movements, however. Like Klaus' Perpetual, the Grande Complication was modular, pairing IWC's revolutionary technology with the common Valjoux 7750 automatic chronograph movement. IWC would produce an entire family of movements on this base, reworking the movement into their Cal. 7900 and 79000 family. But they remained tied to rival Swatch Group's ETA as a movement supplier. This remains one of the most common IWC movements, though IWC switched to Sellita in the 2010s as a supplier of 7750 clones for their Cal. 75000 family.
IWC's other major family of mainstream movements was the time-only Cal. 3000 family. Like the 7900 family, these movements were based on an ETA ebauche: The respected but common ETA 2892. IWC
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