part # 401V4
400 Day Clock Suspension Unit 10C can be identified in the Horolovar 400- Day Repair Guide
The Ollie Baker style mainspring winder includes 9 Steel mainspring sleeves
This set is available in yellow gold fill and sterling silver
Genuine Omega® winding stem
0366 Watch Mainspring 1.20 x 0.08 x 240 (9 1/2 ")(Calibers in description) Omega® 620 part # 401V4Dimensions: 1. 20 x 0. 08 x 240 (9 1 2 ") End Type: Tongue End Material: Swiss Made Unbreakable Fits Calibers: Aurore 10, Aurore 10A, Aurore 10P, Bulova 4AP, Bulova 4P, Bulova 4PP, Bulova 4PR, Bulova PH, Bulova 6CB, Bulova 6CBC, Bulova 6CS, Buren 35, Buren 373, Cyma 052, Cyma 186, Derby 60, General 105, General 106, Liengme 105, Lunesa L25, Movado 105, Omega 19. 4T2, Omega 19. 45, Rolex 1100, Wyler 35