These are parts for AM8 remixed for T-Slot nuts. Using T-slot nuts makes it easier and more flexible. It also makes the parts more efficient by using friction and compression, and removes any tensile force on the mounting holes area since T-slot nut is in direct contact with the parts.
Y-Tensioner is a complete rework and using only one adjustment screw.
Z-Rod holder has provision for 608 ball bearing, or simply use the hole to add constraint to the lead screws. Some would argue that this is bad, but if Z movement is isolated from X movement, this actually help. Mine does, and it shows in my prints. Z moves freely with very little effect on X movements. There is no binding, motors don't work any harder, and lead screws are allowed to move at least 1mm in any direction.