These are holders for a 10x20 cable chain at the Tevo Tarantula.
Using this there are no lose cables hanging around the moving Y/Z axis.
The cables have to be extended in order to connect to the mainboard. Since there is much less movement the soldered joints are no problem and stil flexible enough.
The Y 3 holder uses the end piece of the chain in order to screw down the chain.
I added Y 3-2 which should connect directly to the chain.