Air Fittings

I used to have 2 jobs.
I had tools at both.
I had 2 of the same snap on impact guns / one at each job.
I had to send the one I had at Sears auto center in for repair, so I had to bring the one from the other job with me for a couple of weeks back n forth while I waited for the one to get returned from repair.
The 2 shops used different air fittings.
One day I was quite surprised at the "balls" my impact had at one job and how weak it seemed at the other shop. They both ran the same pressure so I knew it wasn't that. It was the difference in inside diameter of the air fittings that was the difference in how well my impact worked (or didn't)
I used to do a lot of front end/suspension work. So I needed a strong impact. I did a set of struts at my day job and the gun didn't blink, got the strut to knuckle bolts loose without breaking a sweat. .
I brought that gun down to my sears job and had to replace some struts there on a different car and my impact wouldn't touch the bolts that held the struts to the knuckle on that car. The only thing different was that I had to swap fittings in my gun from day job to 2nd job