The 'Thanks Badge' was introduced early in Guiding's history. It is unusual compared to other badges, in that it was designed to be given to members of the public, who were not Guiding members, nor necessarily involved in Guiding at all.
The 1912 handbook states "The Thanks Badge. This has your three green leaves, which stand for your three promises, and between them are the three gleaming moons, of white enamel, which represent a popular emblem, and are typical of what a Guide should be. She shines clear and kindly on a dark night, and sheds a cheery beam to help the wayfarer. She guides the steps of the traveller, and cheers the lonely ones. This badge can be given by a Guide to one who has done her or any Guide a good turn. It means that you wish to thank them, and show your gratitude. A Guide, on seeing someone wearing a 'Thanks Badge' could go up and salute, and ask whether she could be of any assistance."
Although the badge shown hangs from an enameled pin, they can also be found with a plain bar, or without a bar as a brooch.