The needle part on the end of the clothespin now can be swapped easily. Having multiple probe tips allows for different sized needles. In this photo the orange wire probe is a . 2mm needle and the blue wire has a .4mm needle. 

Notches on the probe tip mesh with a 3D printed socket that is glued to the clothespin. Also, there are now two holes for header pins on the copper clad which allow for easy attachment of wires.