Automatic Mainsprings 1.26mm - 1.30mm

Mainspring, 1.30 x 0.075 x 240 x 7.00, AUTOMATIC, ETA 2550 [GR3194-X]

Mainspring, 1.30 x 0.075 x 300 x 7.00, AUTOMATIC, ETA 2671 2670 [GR3197-X]

This will likely require winding into the barrel as although GR list and supply diameter 10.5mm, the…