The top one is clearly the sleeve ferrule. The bottom is the internal (spigot) ferrule. The middle one resembles an internal ferrule, but it’s actually a sleeve ferrule 
Should I called it a “false internal ferrule”, like naming in biology? I like this rod, it deserves a more respectful name 
Ferrules and 3D Prints Revive Classic Microphone - Contrary to what our readers may think, we Hackaday writers aren’t exactly hacking... - https://hackaday.com/2024/03/08/ferrules-and-3d-prints-revive-classic-microphone/ #musicalhacks #strainrelief #microphone #amphenol #balanced #ferrule #unidyne #shure #xlr
