Ship's Telegraph Officer
In Use 1912-1950's
http://www.angelfire.com/wa/dianaspa...tishNavy2.html
Last photo bottom of page.
Post from another forum :
"These were worn throughout MN by officers, warrant and petty officers in WT trades. In the absence of trade badges these were a way of indicating your skills as you moved round your employer's fleet or changed ship and line. Of course they were also backed up by your papers. They were also worn as a button hole badge by leading and ABs, or whatever the line called them, if they were RT/WT trained/qualified."