Variants of stable belts have been around for years. Prior to the claret, light blue and dark blue ones introduced by the Rock Apes in the 1970s, then the RAF wore their very own blue-grey belt, from the 1937 pattern webbing, over War Service Dress as modelled here by Cpl Marsh in Get Some In:
However, at the same time a RAF ceremonial belt in white was issued with a very recognisable buckle in 1937 too:
The more familiar stable belt with the claret (supposed to be the Army), the thin light blue line (supposed to be the RAF) and the dark blue (supposed to be the RN) was introduced by the RAF Regiment in 1970. The colours, the same used on TRFs and previously in the 1920s on RAF head dress, are now enshrined in the RAF. However, the first stable belts had the side fastening - as per all stable belts designed for horse riding and no bulky buckle to rub on the horse during the mount/dis-mount - it was later that the RAF Regiment developed their own belt buckle. Some of the RAF Regiment Squadrons even had their own colour of stable belt in the early days, but uniformity took over and the familiar Rock Ape belt was rolled out in the mid to late ‘70s. Further the RAF Coppers developed their own belt buckle and originally had a black/red stripe only, but again the claret, light blue and dark blue material was used too. The rest of the RAF were then allowed to wear the side fastened stable belt as the Rock Apes had their own now with their crossed rifle logo.
In the early 2000s then a new RAF logo’d belt buckle was released too. This mirrored the RAF Regiment and RAF Police buckles.
So, there is quite a bit of history behind the RAF stable belt. I actually quite like it as an RAF artefact and the colours do make us more recognisable to others that we are RAF. Worn with a barrack shirt and PCS trousers with suitable badges then the RAF identity is maintained. The only people I ever hear gripe about them are the ones that gripe about paying for any item of uniform; the same sort of people who won’t buy a Squadron badge or insist on wearing a beret because they won’t fork out for a smarter field service cap. Fairly strange behaviour from folks who are supposed to have pride in their Service and their appearance.