Grease zerk fitting leaking

I greased all the fittings under the truck. Now I see that the fitting under the trak bar is leaking grease around the ball. I'd like to replace with a new fitting. Anyone know the size I need and is it metric or sae? Thanks
BTW its a 99 cherokee 2wd. Thanks

Pull it out and take it to the store wit you. Probably 1/8"

Ron

I agree with the above advice. I've found that I have both metric and SAE zerks on my '99 XJ. Think it depends on which supplier they happened to get the parts from the day your particular XJ was built...