Rare Trans Mississippi Exposition 1898 Press Pinback WHITEHEAD & HOAG NEWARD N.J

Description

This is a piece that should belong to museum, I have searched all over internet and could not find one like it. Super rare！
The Size: 7/8 inch
Front is Trans- Mississippi Exposition 1898 Press
Back is MADE BY WHITEHEAD & HOAG CO NEWARK, N.J.
The holding metal is broken half way (see photo) but still close it. (see photo).
Shipping: USPS priority with signature require
Thank you for your review, here is little history that I have found.
History
Whitehead & Hoag was founded in 1892 in Newark, New Jersey, by Benjamin S. Whitehead (1858-1940) and Chester R. Hoag (1860-1935) when the two teamed up to combine their expertise and formalize their friendship.
Benjamin Whitehead had studied Printing at the Cooper Union Institute in New York City and first distinguished himself as a printer when his products were exhibited at the 1876 Centennial Exposition in Philadelphia. He was very enterprising, traveled a lot and collected ideas for novelties that he might later produce in his shop.