Excelsior #2877 Mainspring for Angelus Alarm / Travel Clock caliber 190 - ALARM side

Excelsior Mainspring No. 2877 for Angelus Alarm Clock. For ALARM side - Caliber 190 and perhaps others as well, steel, new. See images for precise mainspring specifications.  I specialize in parts for all forms of vintage watches and clocks and all are sold with an unconditional guarantee.  Images to a suitable job of representing the item.