Help ID SAW era pin ID: Army & Navy Union Membership badge

[Chris]

This small pin was with a group of Coast Artillery items I acquired. I can date a couple of the CA items to 1903-1913. But this small badge is a mystery to me. I am hoping the monogram in its center may provide a clue. Any help would be appreciated.

[Salvage Sailor]

USMF Topic --> Army & Navy Union Membership badge

[Chris]

Thanks a bunch.