Hmmm.
I'm going to guess that you are the proud owner of a Velocette motorcycle. The image you've furnished is a tool for it.
The only question is what beast do you have?MSS, VIPER, VENOM, SCRAMBLER, ENDURANCE, CLUBMAN, THRUXTON.
Velocette's were made by Veloce Ltd, in Hall Green, Birmingham. England, 1904 - 1971.
It's not a tool for a Velocette motorcycle,but it's used in the same manner.It's part of a set of various sizes of which this is the largest,3/8" size.
Here's a photo of the whole tool.
Looks like it took a long time for such an easy item... So here another easy one (?)
What is it used for?
Brand name?
Edit: it is not easy, so here are some hints:
Designed (originally) in Europe, company founded in 1932 by a Carpenter.
This stuff comes in different colours, shapes and sizes.