These buttons were worn for a short time only by electricians.
These side buttons were created with the new grade of electrician in the artillery in 1899. They were worn on the Model 1881 dress helmet. In 1901 the Artillery Corps was established, and renamed the Coast Artillery Corps in 1902. Many of the CAC units were the last to receive the new uniform of 1902, and the 1881 pattern helmets were still worn beyond 1902. In this period of time, there were very few electricians in the U.S. Army.
The official period of use for these was from 1899 to 1903. Staple backed.
In fine condition. One button showing a bit more gilt, but so close that on a helmet would be undetectable.