Mean rate 7 ±7 s/day, max. divergence 20 s/day, 3 positions (CH, 6H, 9H); isochronism ±15 s/day. Often marketed as "Special".
Top
0 / +8 s/day
Mean rate 4 ±4 s/day, max. divergence 15 s/day, 5 positions (CH, FH, 6H, 9H, 3H); isochronism ±10 s/day. Often marketed as "Premium".
Chronomètre
-4 / +6 s/day
COSC criteria
Hand-wound 11½-ligne caliber with small seconds at 6 and a date with quick corrector, the manual-wind counterpart of the SW260-1. Sellita technical documentation (version 03, 25.02.2025): case fitting Ø25.60mm (overall Ø26.00mm), 4.35mm high, 23 jewels, 28,800 vph, power reserve minimum 42h / typical 45h, lift angle 50°, Incabloc, stop-second, fine timing device, 3-position stem (running/winding, date correction, time setting).