This is a wooden finger extension worn by Jon Pertwee as the scarecrow Worzel Gummidge. It has been carved to represent a "twiggy finger" and shaped to sit on the end of the actor's finger tip, it still has the pink plaster tape wrapped around it which held it in place.
During and after the run of the UK based first four series and theatre plays, Jon did lots of public appearances at fetes etc dressed in his full costume and makeup. On a visit to Cardiff in 1979, he was handing out preprinted autograph cards to fans (the finger extentions prevented him from signing anything) and when one lady asked to shake his hand this piece "popped off" and he let her keep it "for good luck".