Caliber reference
Sellita SW100-1 caliber: dimensions and drop-in group
The published footprint of the Sellita SW100-1 and which movements share it.
Used in: the Sellita small automatic, the alternative to the ETA 2000-1 in small cases.
A small automatic with date at 20.00 mm x 3.35 mm, Sellita's answer to the ETA 2000-1. It is a compact platform of its own and does not share the 25.60 mm 11 1/2 ligne footprint.
Drop-in group: 8 3/4 ligne small automatic (20.00 mm x 3.35 mm). 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.
Drop-in and related calibers
Donor movement for Sellita SW100-1drop-in lookup
ETA 2000-1 vs Sellita SW100-1drop-in comparison