QUESTION: World War I Horstmann Trench Whistle / Is it linked to Jat Regiment possibly?

[thejman]

Hey guys! New user here and first post,

I was wondering if I could get some help on this trench whistle I have acquired. It is a Horstmann trench whistle made in Philadelphia. On the side, it has been marked fairly lightly reading, "JAT". I know these could be initials of the owner, but I like to entertain the idea that it could have been linked to the Jat Regiment of the British Army. Any ideas? Photos are included. Hope this can spark some discussion, thanks!

IMG_2374.HEIC IMG_2378.heic IMG_2375.HEIC

[thejman]

Sorry, not sure why the original photos came in as HEIC. Here are JPEGs to view without downloading

[SARGE]

Looks like a typical police/military whistle from the turn of the century.  Most police whistles were nickel plated while military ones were brass or bronze like yours.  Often they are marked with either "Police" or "Military".  I can't help with the JAT marking.