My thanks go to Michael Skriletz who kindly send me today’s item for the collection. We looked at the standard khaki version of the Sten Gun sling a few years ago here. Whilst the RAF seem to have used the standard army pattern during the war, in the immediate post war period they must have decided that they wished to emphasis their own uniqueness and so had the slings produced in blue-grey:
In design, the sling is identical to the second wartime pattern and so has a loop at one end to attach the sling to the butt of the Sten:
And a curled wire loop at the other end to attach to the front of the Sten:
A stamped brass buckle is used to adjust the length of the sling:
Details of the manufacturer are stamped faintly onto the webbing, these date it to 1952:

Despite the introduction of the Sterling in 1953, it took at least a decade to roll it out to all branches of the British Armed forces and the RAF would have been low on the list of priorities for replacement, so the Sten and its sling continued to see service throughout the 1950s.
Here a young RAF Airman can be seen guarding a convoy of lorries on a supply run at RAF Kasfareet in the early 1950s with a Sten gun: