Agreed with above, also used on iron.


On certain MP designs the ends of the wire that sits from the front to rear of the block has historically been a minor problem, and would create a small coolant leak to the outside of the block.
The megablock and older MP water block (pre-World) had a small cast-in bump in the front and rear of the block to add material and try to alleviate the problem. Sometimes the strategy did not work and
there would be a spot of porosity or a small gas bubble in the exact location of the wire. I've only seen about a half dozen like that, only one had the leak in the rear.
All were repairable with small pipe plugs but at least a couple were replaced for that reason. It is a very rare failure but did happen.