Thermosetting embossing die depicting the arms of the Royal Air Force (RAF). The Royal Air Force was established on 1 April 1918, essentially a merging of the Royal Flying Corps and the Royal Naval Air Service (RNAS).

This appears to show the RAF badge in use from 1 August 1918 and 1923. The original 1918 design had a circlet which took the form of a garter and buckle and was approved by an Air Council meeting on 1 August 1918. This circlet design proved to be incorrect in terms of heraldry and a slightly revised design with a plain circlet was presented to the College of Arms in 1923. It is the 1923 design which has largely continued through to the present day (2021).