It's a Snapon, and at the end of the handle it'll take an extension. I have an extension as long as the breaker, and I use it all the time on some pretty tight bolts.

I managed to break one of those once....

(Don't jump up and down on the cheater pipe ; P )

I do like SnapOn tho, they gave me a new one (after the guy stopped laughing)

"You did WHAT?....And you think I am going to give you a NEW one?"
"Yes"
"oh..ok, but don't do that again ...."

That is a very nice breaker. The square drive hole is a nice feature.

I also have a couple of those.I have jumped on mine with a pipe and it's held up well.I broke the Craftsman the first time I used it.I did jump on it without a cheater pipe.You can't beat Snap On.

I love my breaker too.  I use it to remove the plug at the top of the water heater each year, so I can blast out each year's accumulated crud with the water hose, draining the waste through the bottom valve out to the woods. 

I used to have two breakers, but I gave one to a friend who also wants to clean out his water heater annually.