Put me into the air operated class as well. Always used a manual grease gun for automotive maintenance. Had a barely used pneumatic grease gun, in the box, sitting for over 20 yrs. Got my first bigger tractor with more grease fittings last year and decided to reach way back to the rear of my storage cabinet and dug it out. Did a quick clean of the head unit, and have been using this old grease pumper ever since. Been thinking of a lock n lube, but the end hose connection fitting is still very tight providing a good grip on the nipples!