Drop-in resolution
Ronda 505 vs Ronda 1005: do they swap?
Whether the Ronda 505 and Ronda 1005 share a case, and what changes if you move between them.
Close in diameter, not a drop-in. The Ronda 505 (23.30 mm case fit (23.90 mm overall) x 3.00 mm) and Ronda 1005 (23.30 mm case fit (23.90 mm overall) x 1.90 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.
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The Ronda 505 is a three-hand Swiss quartz caliber in the 500 family, at the 10 1/2 ligne size. The Ronda 1005 is a three-hand Swiss quartz caliber at the 10 1/2 ligne size, in mid-size quartz watches.
They differ in height (3.00 mm vs 1.90 mm), calendar layout (centre seconds, date at 3, small seconds sub-variant vs centre seconds, date at 3), winding behaviour. A 500-family three-hand quartz caliber at 23.30 mm case fit x 3.00 mm (10 1/2 ligne). It is a size down from the 11 1/2 ligne Ronda 515 and does not fit a 515 case.
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.