The Jubilee Clip was invented and into production in 1921 - post W.W.I, but I saw a pair on a recent Great War German aircraft restoration.
It looks like that's a British trade name - the US equivalent might be 'screw/band hose clamp', but dates to about the same period, by the look.
I'm not sure if there's patent or design differences with the type Holedigger found (different to the Jubilee I've seen) and the other US versions with an offset screw.
See:
http://en.wikipedia.org/wiki/Hose_clamp
http://en.wikipedia.org/wiki/Jubilee_Clip
One of the ways artefacts can be dated in history is the items in construction - stuff that fades from use, stuff that starts getting used, nearly as useful as coins for dating. Generally not critical with warbirds or aviation history, it can be critical in, say ship archaeology. A good aircraft example is the introduction of the Philips or Posidrive screw design, dating original aircraft and often an anachronism in modern restorations.
Does it matter? Not a lot, but production of aircraft would vary depending on the types of screwdrivers used, and the efficiency of the screw design. Industrial heritage can use that data for history and modern analysis...
Still awake?