Mainsprings

Dennison: 8 x 9 1/2 x 13 1/2 Metric 1.70 x .12 x 340mm

Fits Seiko Movement #s: 2501A, 2501B, 2501C 2505A, 2505B, 2516B 2517A, 2517B Measurements: 1.05 x 0.075 x 260 / 1.5 x 13 10.5 (auto)

MSS-WA41 Automatic Mainspring (GR3983X) Swiss Made
White-A-Loy Size 5 1/2 x 10 x 13 3/4 /  1.45 x .11 x 320

6 x 9 1/2 x 12 1/2 White-a-Loy mainspring

4 1/2 x 10 x 11 Swiss Made Mainspring DB End.  1.30 x 0.11 x 280.  GR3281-DB Bestfit MSS-4510KS Fits Poljot/Vostok 2408, 2409, 2409A, 2414, 2414A  

Fits Seiko Movement #s: 3180 Measurements: 1.45 x 0.13 x 420 / 4.5 x 11 x 18.5