Mainsprings

American Pocket Watch Mainsprings

Quality Swiss Made Mainsprings for all popular calibers.

Fits Seiko Movement #s: 394, 395, 400, 603 6201B, 6205B, 6206A, 6206B 6215A, 6216A, 6217A  6218A, 6218B, 6218C 6245A, 6246A Measurements: 1.05 x 0.11 x 360 / 1.5 x 10 x 14.25 (auto)

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)

Fits Seiko Movement #s: 830, 840 4005A, 4006A 8305A, 8306A, 8325A Measurements: 0.95 x 0.12 x 400 / 0.5 x 9.5 x 14.5 (auto)

Fits Seiko Movement #s: 6105 , 6106, 6109 6117 , 6118 , 6119  6138 , 6139  6306, 6309 , 6349

Bestfit White-A-Loy Automatic Mainsprings

Quality Swiss & European Made Generic Mainsprings for popular Omega calibers

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

Quality Swiss Made Generic Rolex Mainsprings for all popular calibers.

8 x 10 x 13 1.70 x .11 x 320 GR4907 Bestfit MS-810N

9 x 11 x 12.5 1.80 x .10 x 320 GR5254 Bestfit MS-911M

9 x 10 x 13.75 1.80 x .11 x 360 GR5278 Bestfit MS-910N

8 x 12 x 11.5 1.70 x .09 x 300 GR4854 Bestfit MS-812K

8 x 12 x 10.5 1.70 x .09 x 260 GR4852 Bestfit MS-812H

7 x 8.5 x 16.75 1.60 x .135 x 420 GR4580 Bestfit MS-785V

7 x 15 x 9.5 1.60 x .06 x 240 GR4413 Bestfit MS-715E

7 x 13 x 9.5 1.60 x 0.08 x 240 GR4445 Bestfit MS-713E

7 x 12 x 10.5 1.60 x 0.09 x 260 GR4463 Bestfit MS-712H

7 x 11 x 12.5 1.60 x 0.10 x 320 GR4487 Bestfit MS-711M

7 x 10 x 10.5 1.60 x 0.105 x 240 GR4500 Bestfit MS-710H

6 x 9.5 x 12.5 1.50 x 0.12 x 320 GR4176 Bestfit MS-695M

6 x 9.5 x 10.5 1.50 x 0.12 x 260 GR4173 Bestfit MS-695H

6 x 15 x 7.5 1.50 x 0.06 x 200 GR4041 Bestfit MS-615A