Vintage Thing No.7 - An obscure special tool

It was some of my neighbours who coined the term Vintage Thing and this is the, er, Vintage Thing that prompted that remark. They were having a garage clear out and this emerged, metaphorically blinking in the sunlight.

It's a special tool of some sort made by Churchill, serial number 18G927C.

Nobody knows what it fits but somebody somewhere is probably, at this very moment, crying out for this Vintage Thing. To throw it away would seem to be a crime so I took pity on it and it has now come to live with me at the Cornish Repository for Unwanted Vintage Things until it can be rehomed.