ITW Ramset Drive pins .300 headed for powder actuated tools 0.145 inches diameter knurled shank boxed length. 100 per box Caution: Always wear eye and ear protection at all times. If you aren't sure which power level to use then start with a lower level and work your way up. And remember that 1" of penetration into concrete is the rule of thumb. And yes, with the proper power level and correct length you can fasten to structural steel. But beware the noise and the recoil.