Lock core pulling tool. 1:17 video:
https://www.youtube.com/watch?v=bi1lMG3Lfmc
More: https://www.zieh-fix.com/en/zieh-fixr-glocke.html
Previously:
https://www.homemadetools.net/forum/...990#post100427
https://www.homemadetools.net/forum/...490#post142913
https://www.homemadetools.net/forum/...471#post142836
https://www.homemadetools.net/forum/...519#post135921
https://www.homemadetools.net/forum/...793#post136975
https://www.homemadetools.net/forum/...780#post133199