Several British knuckleduster designs emerged in the first half of the 20th Century, and they saw service with cops and criminals alike, as well as going to war, and even carried by Winston Churchill's body guard. The example shown here is the most common shape I have encountered, it is cast brass, patina from age. The beauty of this design is comfort while wearing and lack of bite while striking. The finger stalls (holes) are meant to accommodate specific fingers and definitely feels most comfortable when oriented correctly. The stalls are slightly larger at the top so finger knuckles can pass through and the finger can come down to rest on the softly curved stall bottom. The palm swell has just the right distance from the stalls to enable ones fist to close and feel natural. Designed and fashioned by an obviously skilled craftsman, the British Knuckleduster was easy to replicate and so was produced from before WWI up to WWII.