Hello Corte Your most "explicit" description has allowed my addled brain access to the niceties of this "wunder-tool"! I imagine there must be a two-part stem which, coming to the end of its circular motion, engages impact-wise on that part which is on the wrest pin. Have I got the general idea? Sounds quite ingenious! Why is this tool not more widely known and accepted? Regards Michael G (UK) just after 8 pm on a Dark and Gloomy night in the Sussex Downlands...
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