Well, it is a little gun...well, I guess a big gun, but little or "light" to welding standards that tac welds a stud where you desire...quick, light tac. You can then grab on to that stud with a slid hammer and tap out your dent. This is opposed to the old method of drilling a hole and twisting a body bit into the hole, grabing it with the slide hammer and pulling it out. Both are ways to grab the metal to pull out the dent, just the tac weld method doesn't require drilling to perform the task.
