Bird
Rest in Peace
It refers to an external grease fitting which I haven't located yet.
Alan, it's part #17 in the parts list and exploded view. Look on the side of the hammer case (front housing) and you'll see what looks like (and is) a tiny ball bearing in a dimple. That's the grease fitting. You have to have a needle nosed grease gun to inject grease there. Naturally, Ingersoll-Rand mades a special grease for that, but the fact is that most folks probably never add grease. For a mechanic, using it all the time, I'd recommend you get the right grease and grease gun, but in your case, it may not need any additional grease for the next 10 years.