EB 8370-66 – interchangeable spare parts

EB 8370-66 movement

Which spare parts fit the EB 8370-66 movement? For every part you can see which other calibers use the same part according to the original interchangeability list.

28Parts with interchange data

56Calibers sharing parts

Note: We have compiled this overview to the best of our knowledge and belief, based on the original interchangeability lists of EB and the original spare-part labels. All information has been carefully checked but is provided without guarantee. Please verify the interchangeability yourself before fitting, especially the height, diameter and execution of the part.

🛒 Spare parts for EB 8370-66 in our shop

Bettlach EB 8370 Balance without Hairspring for EB 8370-66, 8374, 8376-67 – NOS12,90 € incl. VAT *View item ›

Bettlach EB 8370 Balance Complete for EB 8370-66, 8370-67, 8374, 8376-67 – Part 79321,90 € incl. VAT *View item ›

🔧 Interchangeable parts

Part no.	Description	Also fits
163/1ISO 80.400	Center pipe	EB 8320 EB 8320-66 EB 8320-67 EB 8321 EB 8321-66 EB 8321-67 EB 8330-66 EB 8330-67 EB 8331-66 EB 8331-67 EB 8340 EB 8340-66 EB 8340-67 EB 8341 EB 8341-66 EB 8341-67 EB 8370 EB 8370-67 EB 8371-67 EB 8381 EB 8381-66 EB 8381-67 EB 8391-66 EB 8391-67 Height 135 EB 8320 EB 8320-66 EB 8320-67 EB 8321 EB 8321-66 EB 8321-67 EB 8330-66 EB 8330-67 EB 8331-66 EB 8331-67 EB 8340 EB 8340-66 EB 8340-67 EB 8341 EB 8341-66 EB 8341-67 EB 8370 EB 8370-67 EB 8371-67 EB 8381 EB 8381-66 EB 8381-67 EB 8391-66 EB 8391-67
181/1ISO 20.040.06	Barrel for drilled core with driving wheel / driving pinion	EB 8370 2e EB 8374-66 EB 8376-66 EB 8381 EB 8381-66 EB 8385-66 EB 8387-66 EB 8391-66 EB 8395-66 EB 8397-66
197ISO 20.070.06	Core and ratchet wheel, riveted	EB 8370 2e EB 8370-67 EB 8371-67 EB 8374-66 EB 8374-67 EB 8376-66 EB 8376-67 EB 8381 EB 8381-66 EB 8381-67 EB 8385-66 EB 8385-67 EB 8387-66 EB 8387-67 EB 8391-66 EB 8391-67 EB 8395-66 EB 8395-67 EB 8397-66 EB 8397-67 EB 8398-67
199ISO 20.062	Barrel axle	EB 8320 EB 8320-66 EB 8320-67 EB 8321 EB 8321-66 EB 8321-67 EB 8330-66 EB 8330-67 EB 8331-66 EB 8331-67 EB 8340 EB 8340-66 EB 8340-67 EB 8341 EB 8341-66 EB 8341-67 EB 8350 EB 8350-66 EB 8350-67 EB 8354-66 EB 8354-67 EB 8361 EB 8361-66 EB 8361-67 EB 8364-67 EB 8365-66 EB 8365-67 EB 8370 EB 8370-67 EB 8371-67 EB 8374-66 EB 8374-67 EB 8376-66 EB 8376-67 EB 8381 EB 8381-66 EB 8381-67 EB 8385-66 EB 8385-67 EB 8387-66 EB 8387-67 EB 8391-66 EB 8391-67 EB 8395-66 EB 8395-67 EB 8397-66 EB 8397-67 EB 8398-67
203ISO 30.012	Intermediate wheel and pinion	EB 8320 EB 8320-66 EB 8320-67 EB 8321 EB 8321-66 EB 8321-67 EB 8330-66 EB 8330-67 EB 8331-66 EB 8331-67 EB 8340 EB 8340-66 EB 8340-67 EB 8341 EB 8341-66 EB 8341-67 EB 8350 EB 8350-66 EB 8350-67 EB 8354-66 EB 8354-67 EB 8361 EB 8361-66 EB 8361-67 EB 8365-66 EB 8365-67 EB 8370 EB 8370-67 EB 8371-67 EB 8374-66 EB 8374-67 EB 8376-66 EB 8376-67 EB 8381 EB 8381-66 EB 8381-67 EB 8385-66 EB 8385-67 EB 8387-66 EB 8387-67 EB 8391-66 EB 8391-67 EB 8395-66 EB 8395-67 EB 8397-66 EB 8397-67 EB 8398-67
210ISO 30.025	Third wheel	EB 8320 EB 8320-66 EB 8320-67 EB 8321 EB 8321-66 EB 8321-67 EB 8330-67 EB 8331-66 EB 8331-67 EB 8340 EB 8340-66 EB 8340-67 EB 8341 EB 8341-66 EB 8341-67 EB 8350 EB 8350-66 EB 8350-67 EB 8354-66 EB 8354-67 EB 8361 EB 8361-66 EB 8361-67 EB 8364-67 EB 8365-66 EB 8365-67 EB 8370 EB 8370-67 EB 8371-67 EB 8374-66 EB 8374-67 EB 8376-66 EB 8376-67 EB 8381 EB 8381-66 EB 8381-67 EB 8385-66 EB 8385-67 EB 8387-66 EB 8387-67 EB 8391-66 EB 8391-67 EB 8395-66 EB 8395-67 EB 8397-66 EB 8397-67 EB 8398-67
224ISO 30.027.13	Fourth wheel	EB 8350 EB 8350-66 EB 8350-67 EB 8370 EB 8370-67 Height 454 EB 8350 EB 8350-66 EB 8350-67 EB 8370 EB 8370-67
243/1ISO 31.081.18	Cannon pinion, undrilled, without clam notch, smooth hole	EB 8320 EB 8320-66 EB 8320-67 EB 8330-66 EB 8330-67 EB 8340 EB 8340-66 EB 8340-67 EB 8350 EB 8350-66 EB 8350-67 EB 8370 EB 8370-67 Height 215 EB 8320 EB 8320-66 EB 8320-67 EB 8330-66 EB 8330-67 EB 8340 EB 8340-66 EB 8340-67 EB 8350 EB 8350-66 EB 8350-67 EB 8370 EB 8370-67 Height 245 EB 8320 EB 8320-66 EB 8320-67 EB 8330-66 EB 8330-67 EB 8340 EB 8340-66 EB 8340-67 EB 8350 EB 8350-66 EB 8350-67 EB 8370 EB 8370-67
250ISO 31.046	Hour wheel	EB 8320 EB 8320-66 EB 8320-67 EB 8321 EB 8321-66 EB 8321-67 EB 8330-66 EB 8330-67 EB 8331-66 EB 8331-67 EB 8340 EB 8340-66 EB 8340-67 EB 8341 EB 8341-66 EB 8341-67 EB 8361 EB 8361-66 EB 8361-67 EB 8370 EB 8370-67 EB 8381 EB 8381-66 EB 8381-67 EB 8391-66 EB 8391-67 Height 117 EB 8320 EB 8320-66 EB 8320-67 EB 8321 EB 8321-66 EB 8321-67 EB 8330-66 EB 8330-67 EB 8331-66 EB 8331-67 EB 8340 EB 8340-66 EB 8340-67 EB 8341 EB 8341-66 EB 8341-67 EB 8361 EB 8361-66 EB 8361-67 EB 8370 EB 8370-67 EB 8381 EB 8381-66 EB 8381-67 EB 8391-66 EB 8391-67 Height 150 EB 8320 EB 8320-66 EB 8320-67 EB 8321 EB 8321-66 EB 8321-67 EB 8330-66 EB 8330-67 EB 8331-66 EB 8331-67 EB 8340 EB 8340-66 EB 8340-67 EB 8341 EB 8341-66 EB 8341-67 EB 8361 EB 8361-66 EB 8361-67 EB 8370 EB 8370-67 EB 8381 EB 8381-66 EB 8381-67 EB 8391-66 EB 8391-67
260ISO 31.041	Minute wheel	EB 8320 EB 8320-66 EB 8320-67 EB 8321 EB 8321-66 EB 8321-67 EB 8330-66 EB 8330-67 EB 8331-66 EB 8331-67 EB 8340 EB 8340-66 EB 8340-67 EB 8341 EB 8341-66 EB 8341-67 EB 8350 EB 8350-66 EB 8350-67 EB 8354-66 EB 8354-67 EB 8361 EB 8361-66 EB 8361-67 EB 8364-67 EB 8365-66 EB 8365-67 EB 8370 EB 8370-67 EB 8371-67 EB 8374-66 EB 8374-67 EB 8376-66 EB 8376-67 EB 8381 EB 8381-66 EB 8381-67 EB 8385-66 EB 8385-67 EB 8387-66 EB 8387-67 EB 8391-66 EB 8391-67 EB 8395-66 EB 8395-67 EB 8397-66 EB 8397-67 EB 8398-67
307ISO 40.301	Regulator with adjustable stud holder, for flat hairspring	EB 8370 EB 8370-67 EB 8371-67 EB 8374-66 EB 8374-67 EB 8376-66 EB 8376-67 EB 8381 EB 8381-66 EB 8381-67 EB 8385-66 EB 8385-67 EB 8387-66 EB 8387-67 EB 8391-66 EB 8391-67 EB 8395-66 EB 8395-67 EB 8397-66 EB 8397-67 EB 8398-67
311ISO 70.800	Upper cap jewel with end-piece	EB 8320 EB 8320-66 EB 8320-67 EB 8321 EB 8321-66 EB 8321-67 EB 8330-66 EB 8330-67 EB 8331-66 EB 8331-67 EB 8340 EB 8340-66 EB 8340-67 EB 8341 EB 8341-66 EB 8341-67 EB 8350 EB 8350-66 EB 8350-67 EB 8354-66 EB 8354-67 EB 8361 EB 8361-66 EB 8361-67 EB 8364-67 EB 8365-66 EB 8365-67 EB 8370 EB 8370-67 EB 8371-67 EB 8374-66 EB 8374-67 EB 8376-66 EB 8376-67 EB 8381 EB 8381-66 EB 8381-67 EB 8385-66 EB 8385-67 EB 8387-66 EB 8387-67 EB 8391-66 EB 8395-66 EB 8395-67 EB 8397-66 EB 8397-67 EB 8398-67 EB 9391-67
330ISO 70.801	Lower cap jewel with end-piece	EB 8320 EB 8320-66 EB 8320-67 EB 8321 EB 8321-66 EB 8321-67 EB 8330-66 EB 8330-67 EB 8331-66 EB 8331-67 EB 8340 EB 8340-66 EB 8340-67 EB 8341 EB 8341-66 EB 8341-67 EB 8350 EB 8350-66 EB 8350-67 EB 8354-66 EB 8354-67 EB 8361 EB 8361-66 EB 8361-67 EB 8364-67 EB 8365-66 EB 8365-67 EB 8370 EB 8370-67 EB 8371-67 EB 8374-66 EB 8374-67 EB 8376-66 EB 8376-67 EB 8381 EB 8381-66 EB 8381-67 EB 8385-66 EB 8385-67 EB 8387-66 EB 8387-67 EB 8391-66 EB 8391-67 EB 8395-66 EB 8395-67 EB 8397-66 EB 8397-67 EB 8398-67
401ISO 51.010	Winding stem	EB 8320 EB 8320-66 EB 8321 EB 8321-66 EB 8330-66 EB 8331-66 EB 8340 EB 8340-66 EB 8341 EB 8341-66 EB 8350 EB 8350-66 EB 8354-66 EB 8361 EB 8361-66 EB 8365-66 EB 8370 EB 8374-66 EB 8376-66 EB 8381 EB 8381-66 EB 8385-66 EB 8387-66 EB 8391-66 EB 8395-66 EB 8397-66
407ISO 31.121	Clutch wheel	EB 8320 EB 8320-66 EB 8320-67 EB 8321 EB 8321-66 EB 8321-67 EB 8330-66 EB 8330-67 EB 8331-66 EB 8331-67 EB 8340 EB 8340-66 EB 8340-67 EB 8341 EB 8341-66 EB 8341-67 EB 8350 EB 8350-66 EB 8350-67 EB 8354-66 EB 8354-67 EB 8361 EB 8361-66 EB 8361-67 EB 8364-67 EB 8365-66 EB 8365-67 EB 8370 EB 8370-67 EB 8371-67 EB 8374-66 EB 8374-67 EB 8376-66 EB 8376-67 EB 8381 EB 8381-66 EB 8381-67 EB 8385-66 EB 8385-67 EB 8387-66 EB 8387-67 EB 8391-66 EB 8391-67 EB 8395-66 EB 8395-67 EB 8397-66 EB 8397-67 EB 8398-67
410ISO 31.120	Winding pinion	EB 8320 EB 8320-66 EB 8320-67 EB 8321 EB 8321-66 EB 8321-67 EB 8330-66 EB 8330-67 EB 8331-66 EB 8331-67 EB 8340 EB 8340-66 EB 8340-67 EB 8341 EB 8341-66 EB 8341-67 EB 8350 EB 8350-66 EB 8350-67 EB 8354-66 EB 8354-67 EB 8361 EB 8361-66 EB 8361-67 EB 8364-67 EB 8365-66 EB 8365-67 EB 8370 EB 8370-67 EB 8371-67 EB 8374-66 EB 8374-67 EB 8376-66 EB 8376-67 EB 8381 EB 8381-66 EB 8381-67 EB 8385-66 EB 8385-67 EB 8387-66 EB 8387-67 EB 8391-66 EB 8391-67 EB 8395-66 EB 8395-67 EB 8397-66 EB 8397-67 EB 8398-67
420ISO 31.023	Crown wheel	EB 8320 EB 8320-66 EB 8320-67 EB 8321 EB 8321-66 EB 8321-67 EB 8330-66 EB 8330-67 EB 8331-66 EB 8331-67 EB 8340 EB 8340-66 EB 8340-67 EB 8341 EB 8341-66 EB 8341-67 EB 8350 EB 8350-66 EB 8350-67 EB 8354-66 EB 8354-67 EB 8361 EB 8361-66 EB 8361-67 EB 8364-67 EB 8365-66 EB 8365-67 EB 8370 EB 8370-67 EB 8371-67 EB 8374-66 EB 8374-67 EB 8376-66 EB 8376-67 EB 8381 EB 8381-66 EB 8381-67 EB 8385-66 EB 8385-67 EB 8387-66 EB 8387-67 EB 8391-66 EB 8391-67 EB 8395-66 EB 8395-67 EB 8397-66 EB 8397-67 EB 8398-67
425ISO 51.120	Click	EB 8320 EB 8320-66 EB 8320-67 EB 8321 EB 8321-66 EB 8321-67 EB 8330-66 EB 8330-67 EB 8331-66 EB 8331-67 EB 8340 EB 8340-66 EB 8340-67 EB 8341 EB 8341-66 EB 8341-67 EB 8350 EB 8350-66 EB 8350-67 EB 8354-66 EB 8354-67 EB 8361 EB 8361-66 EB 8361-67 EB 8364-67 EB 8365-66 EB 8365-67 EB 8370 EB 8370-67 EB 8371-67 EB 8374-66 EB 8374-67 EB 8376-66 EB 8376-67 EB 8381 EB 8381-66 EB 8381-67 EB 8385-66 EB 8385-67 EB 8387-66 EB 8387-67 EB 8391-66 EB 8391-67 EB 8395-66 EB 8395-67 EB 8397-66 EB 8397-67 EB 8398-67
430ISO 61.080	Click spring	EB 8320 EB 8320-66 EB 8320-67 EB 8321 EB 8321-66 EB 8321-67 EB 8330-66 EB 8330-67 EB 8331-66 EB 8331-67 EB 8340 EB 8340-66 EB 8340-67 EB 8341 EB 8341-66 EB 8341-67 EB 8350 EB 8350-66 EB 8350-67 EB 8354-66 EB 8354-67 EB 8361 EB 8361-66 EB 8361-67 EB 8364-67 EB 8365-66 EB 8365-67 EB 8370 EB 8370-67 EB 8371-67 EB 8374-66 EB 8374-67 EB 8376-66 EB 8376-67 EB 8381 EB 8381-66 EB 8381-67 EB 8385-66 EB 8385-67 EB 8387-66 EB 8387-67 EB 8391-66 EB 8391-67 EB 8395-66 EB 8395-67 EB 8397-66 EB 8397-67 EB 8398-67
435/1ISO 51.050	Spring yoke	EB 8320 EB 8320-66 EB 8321 EB 8321-66 EB 8330-66 EB 8331-66 EB 8340 EB 8340-66 EB 8341 EB 8341-66 EB 8350 EB 8350-66 EB 8354-66 EB 8361 EB 8361-66 EB 8365-66 EB 8370 EB 8374-66 EB 8376-66 EB 8381 EB 8381-66 EB 8385-66 EB 8387-66 EB 8391-66 EB 8395-66 EB 8397-66
443/1ISO 51.080.06	Setting lever, assembled	EB 8320-66 EB 8321-66 EB 8330-66 EB 8331-66 EB 8340-66 EB 8341-66 EB 8350-66 EB 8354-66 EB 8361-66 EB 8365-66 EB 8374-66 EB 8376-66 EB 8381-66 EB 8385-66 EB 8387-66 EB 8391-66 EB 8395-66 EB 8397-66
450ISO 31.100	Setting wheel	EB 8135 EB 8137 EB 8320 EB 8320-66 EB 8320-67 EB 8321 EB 8321-66 EB 8321-67 EB 8330-66 EB 8330-67 EB 8331-66 EB 8331-67 EB 8340 2e EB 8340-66 EB 8340-67 EB 8341 EB 8341-66 EB 8341-67 EB 8350 EB 8350-66 EB 8350-67 EB 8354-66 EB 8354-67 EB 8361 EB 8361-66 EB 8361-67 EB 8364-67 EB 8365-66 EB 8365-67 EB 8370 EB 8370-67 EB 8371-67 EB 8374-66 EB 8374-67 EB 8376-66 EB 8376-67 EB 8381 EB 8381-66 EB 8381-67 EB 8385-66 EB 8385-67 EB 8387-66 EB 8387-67 EB 8391-66 EB 8391-67 EB 8395-66 EB 8395-67 EB 8397-66 EB 8397-67 EB 8398-67 1st execution EB 8115 EB 8135 EB 8137 EB 8320 EB 8320-66 EB 8320-67 EB 8321 EB 8321-66 EB 8321-67 EB 8330-66 EB 8330-67 EB 8331-66 EB 8331-67 EB 8340 2e EB 8340-66 EB 8340-67 EB 8341 EB 8341-66 EB 8341-67 EB 8350 EB 8350-66 EB 8350-67 EB 8354-66 EB 8354-67 EB 8361 EB 8361-66 EB 8361-67 EB 8364-67 EB 8365-66 EB 8365-67 EB 8370 EB 8370-67 EB 8371-67 EB 8374-66 EB 8374-67 EB 8376-66 EB 8376-67 EB 8381 EB 8381-66 EB 8381-67 EB 8385-66 EB 8385-67 EB 8387-66 EB 8387-67 EB 8391-66 EB 8391-67 EB 8395-66 EB 8395-67 EB 8397-66 EB 8397-67 EB 8398-67
790ISO 30.041	Pin escape wheel, pivoted	EB 8320 EB 8320-66 EB 8320-67 EB 8321 EB 8321-66 EB 8321-67 EB 8330-66 EB 8330-67 EB 8331-66 EB 8331-67 EB 8340 EB 8340-66 EB 8340-67 EB 8341 EB 8341-66 EB 8341-67 EB 8350 EB 8350-66 EB 8350-67 EB 8354-66 EB 8354-67 EB 8361 EB 8361-66 EB 8361-67 EB 8364-67 EB 8365-66 EB 8365-67 EB 8370 EB 8370-67 EB 8371-67 EB 8374-66 EB 8374-67 EB 8376-66 EB 8376-67 EB 8381 EB 8381-66 EB 8381-67 EB 8385-66 EB 8385-67 EB 8387-66 EB 8387-67 EB 8391-66 EB 8391-67 EB 8395-66 EB 8395-67 EB 8397-66 EB 8397-67 EB 8398-67
792ISO 41.101.41	Balance staff for roller	EB 8320 EB 8320-66 EB 8320-67 EB 8321 EB 8321-66 EB 8321-67 EB 8330-66 EB 8330-67 EB 8331-66 EB 8331-67 EB 8340 EB 8340-66 EB 8340-67 EB 8341 EB 8341-66 EB 8341-67 EB 8350 EB 8350-66 EB 8350-67 EB 8354-66 EB 8354-67 EB 8361 EB 8361-66 EB 8361-67 EB 8364-67 EB 8365-66 EB 8365-67 EB 8370 EB 8370-67 EB 8371-67 EB 8374-66 EB 8374-67 EB 8376-66 EB 8376-67 EB 8381 EB 8381-66 EB 8381-67 EB 8385-66 EB 8385-67 EB 8387-66 EB 8387-67 EB 8391-66 EB 8391-67 EB 8395-66 EB 8395-67 EB 8397-66 EB 8397-67 EB 8398-67
793ISO 40.054	Balance with roller, regulated	EB 8370 EB 8370-67 EB 8371-67 EB 8374-66 EB 8374-67 EB 8376-66 EB 8376-67 EB 8370 EB 8370-67 EB 8371-67 EB 8374-66 EB 8374-67 EB 8376-66 EB 8376-67
794ISO 40.055	Balance with finger, regulated	EB 8370 EB 8370-67 EB 8371-67 EB 8374-66 EB 8374-67 EB 8376-66 EB 8376-67 EB 8381 EB 8381-66 EB 8381-67 EB 8385-66 EB 8385-67 EB 8387-66 EB 8387-67 EB 8391-66 EB 8391-67 EB 8395-66 EB 8395-67 EB 8397-66 EB 8397-67 EB 8398-67
799/4ISO 40.123	Small roller	EB 8370 EB 8370-67 EB 8371-67 EB 8374-66 EB 8374-67 EB 8376-66 EB 8376-67 EB 8381 EB 8381-66 EB 8381-67 EB 8385-66 EB 8385-67 EB 8387-66 EB 8387-67 EB 8391-66 EB 8391-67 EB 8395-66 EB 8395-67 EB 8397-66 EB 8397-67 EB 8398-67
821/792ISO 40.101.26	Balance staff for roller and for shock-protecting device	EB 8135 EB 8137 EB 8155 EB 8157 EB 8175 EB 8177 EB 8320 EB 8320-66 EB 8320-67 EB 8321 EB 8321-66 EB 8321-67 EB 8330-66 EB 8330-67 EB 8331-66 EB 8331-67 EB 8340 EB 8340-66 EB 8340-67 EB 8341 EB 8341-66 EB 8341-67 EB 8350 EB 8350-66 EB 8350-67 EB 8354-66 EB 8354-67 EB 8361 EB 8361-66 EB 8361-67 EB 8364-67 EB 8365-66 EB 8365-67 EB 8370 EB 8370-67 EB 8371-67 EB 8374-66 EB 8374-67 EB 8376-66 EB 8376-67 EB 8381 EB 8381-66 EB 8381-67 EB 8385-66 EB 8385-67 EB 8387-66 EB 8387-67 EB 8391-66 EB 8391-67 EB 8395-66 EB 8395-67 EB 8397-66 EB 8397-67 EB 8398-67

Source: original interchangeability lists of EB (checked transcription) and checked original spare-part labels · as of 2026-10-28. Height / execution: the part fits only in this height or execution.

🌀 Matching mainspring

Mainspring dimensions for EB 8370-66 (height × diameter × thickness × length) and matching mainspring in our shop:

EB 8370-66: 1.50 × 10.0 × 0.125 × 320 mm (GR 4184-1)

🔗 Movements sharing the most parts

→ All calibers of EB

❓ Frequently asked questions

Which EB 8370-66 spare parts also fit other movements?

For the EB 8370-66, 28 part numbers are listed as interchangeable. Together they fit 56 other calibers – the table below shows which part fits which movement.

Which movements share the most parts with the EB 8370-66?

The most shared parts: EB 8370 (35 parts), EB 8370-67 (32 parts), EB 8381-66 (29 parts).

Which mainspring fits the EB 8370-66?

According to the Générale Ressorts catalogue (height × diameter × thickness × length): 1.50 × 10.0 × 0.125 × 320 mm (GR 4184-1, hand-wound, special version (1)).