I'm not really sure there's a definition of "heavy duty" for me to compare this thing to. But it seems well made. I stapled the bejesus out of some pine bed slats during which which it performed admirably. I never had any jams and the staples penetrated the wood completely, but others have complained. The loading mechanism is weird and is an excellent opportunity to pinch your finger, but overall it seemed to be a fine staple gun to me.