1 x Replacement Watch Mainspring 

Elgin 857
(may fit others but check your spring measurements first)

Dimensions:
2.90 x 0.23 x 520 x 20mm

Mainspring type:
Special Bridle

Quantity supplied: 1 spring

If you are unsure if you need this part please email us first and we will do our best to point you in the right direction