Actually, they are zinc rods inserted into a bolt that fits in the engine
drain holes in the cylinder.
They are larger than the stock plugs, so you have to drill and tap the drain
holes.
It is difficult to do this on the left side of the motor as the pushrod tube
blocks part of the drain hole.

Todd
'88 Westy

"Sean B." wrote:

> I haven't looked into it too carefully, but Fast German Auto touts a
> product they call "Z-sticks" which (I believe) are basically zinc head
> studs. They say that these are supposed to help with the corrosion issues.
>
> Sean B.
> '90 V'gon, "Happy Bus", pseudo Wolfy
> Torrance, CA