Drop-in resolution
Donor movement for the ETA Valjoux 7750
Which movement drops into a ETA Valjoux 7750 case, and what has to match beyond the footprint.
Drop-in available. The Sellita SW500 shares the ETA Valjoux 7750 footprint (30.00 mm x 7.90 mm, chronograph, subdials at 6-9-12, day and date at 3) and is the standard donor.
The ETA Valjoux 7750 sits in the 7750 chronograph footprint, 6-9-12 (30.00 mm x 7.90 mm) group. The Sellita SW500 share its casing diameter, height and calendar layout, so a case and dial built for the ETA Valjoux 7750 accept them with the correct dial and hands.
Matching diameter and height is necessary but not sufficient. A donor is only a true drop-in when the dial-foot positions, hand-hole sizes, stem length and calendar layout also match. Two movements can share a case and still need a new dial, re-broached hands or a cut-to-length stem.