Caliber reference
ETA 955.112 caliber: dimensions and drop-in group
The published footprint of the ETA 955.112 and which movements share it.
Used in: a common Swiss three-hand quartz caliber, the ETA rival to the Ronda 515.
A Swiss three-hand date quartz caliber at 25.60 mm x 3.15 mm sharing the 11 1/2 ligne diameter. It is not a mechanical donor: replacing an automatic with it changes power source and hand heights entirely. It competes with the Ronda 515 at the same diameter.
Drop-in group: ETA 11 1/2 quartz three-hand (25.60 mm x 3.15 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.