In 1910 it was agreed that men of the Territorial Army who had volunteered to serve overseas should be awarded a small badge to show that they had made this commitment. The Army Order stated:

1. His Majesty the King has been graciously pleased to approve of (a)- A badge being worn in the right breast of officers and men of the Territorial Force when in uniform who take the liability to serve outside the United Kingdom in time of national emergency…(b) Each Territorial Force Unit, 90 percent of whose serving members are under such liability, having that fact recorded in a suitable manner under its title in the Army list.
2. The badge will be a metal tablet 1 5/8″ by 2/5″ , bearing the words “Imperial Service” in raised letters and surmounted by a crown 3/5″ high.

By 1913 7% of the Territorial Force had signed up and were issued the badge, made of either cupro-nickel or brass and very occasionally silver:

This example is in very poor condition and is missing the pin fitting on the back that allowed it to be worn:

The badges are easily spotted in period photographs, being worn above the right service dress jacket’s pocket: