Suit Nissan Patrol Y61 GU with the RD28 and the ZD30DI engine up to 11/2002.
This is the Cap that screws into the fill Hole in the rocker cover.
And Comes with a new O'Ring fitted.
There are 2 lengths of thread with these caps, this is the Shorter option.
The Distance from the end of the thread to the Oring is 10mm