Drop-in resolution
Sellita SW330-1 vs Miyota 82S0: do they swap?
Whether the Sellita SW330-1 and Miyota 82S0 share a case, and what changes if you move between them.
Close in diameter, not a drop-in. The Sellita SW330-1 (25.60 mm x 4.10 mm) and Miyota 82S0 (26.00 mm x 5.67 mm) are near in size but differ in height, dial feet or layout, so moving between them means a new dial, hands and often a case adjustment.
The Sellita SW330-1 is the Sellita caller-GMT automatic, the drop-in alternative to the ETA 2893-2. The Miyota 82S0 is the open-heart 8200 member with a skeletonised balance aperture at 7.
They differ in diameter (25.60 mm vs 26.00 mm), height (4.10 mm vs 5.67 mm), beat rate (28,800 A/h (4 Hz) vs 21,600 A/h (3 Hz)), calendar layout (centre seconds, GMT 24h hand, date at 3 vs centre seconds, open heart at 7, no date), winding behaviour. Built to the 2893-2 GMT footprint at 25.60 mm x 4.10 mm with a caller-style GMT hand and date at 3. It carries four more jewels than the ETA (25 vs 21) and is the standard donor when a 2893-2 is unavailable.
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.