Not short, short!
"The body itself is short but for some reason the mounting bracket is quite long, much longer than the one it is replacing? The part fits as it should and works as it should, that's the main thing, but as it's a folding bike with only 20" wheels the lenght of the derailleur is crucial as the lower jockey wheels gets worryingly close to the ground. Used everyday for six days cycling around part of France with no issues."