This is a chrome on brass mudguard trim, its a copy of an original available back in the sixties on Andre Baldet scooters, its so smart and different .
Its to fit the G.S. model mudguards but my supplier said they had fitted one to a series 2? you can even take the top off and fit it to a lammy mudguard(2nd pic.) and where theres a will so to speak
appx. six inches long at the bottom and the bullet type top is about appx. 4 inches. They called it the "Meteor".