on the parts listing at ford it has some 'krytex', err spelling, grease inbetween the spark plug and the coil for ba's.

what is this?
just water proofing?

is it necessary?

what can i use thats available at repco/bursons etc as a subsitute?

the parts bloke didn't know what it was and didn't have any on hand to show me.

Thanks for help.