Sellita SW240-1 caliber: dimensions and drop-in group

Used in: a Sellita automatic with small seconds at 6, in dress and field watches with a sub-dial.

An automatic 11 1/2 ligne caliber with small seconds at 6 and date at 3 at 25.60 mm x 4.60 mm. It needs a small-seconds dial and is not interchangeable with a centre-seconds SW200-1.

Drop-in group: 11 1/2 ligne automatic small seconds at 6 (25.60 mm x 4.60 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.