The Winchester Thumb Trigger rifle was a very inexpensive boy's rifle developed from the Model 1902. It is a single-shot .22 rimfire bolt action system, on which the trigger was replaced by a thumb-activated sear behind the bolt. In theory, this was to allow greater accuracy by requiring less force acting to disrupt your point of aim when firing. It was also a simpler and thus cheaper mechanism to manufacture. About 75,000 of these rifles were sold, including many exported to Australia, interestingly.