They're technical pens developed for architects and the like. They have a needle-type point and come in different line widths. Architects don't use them as much now that they have software, (unless they're "old school") but artists do. They make it possible for you to apply a very thin, very even ink line, great for effects like the crosshatching that was used in that sketch of Steele.
That's the good news. On the other hand they aren't cheap and they aren't fun to clean when they clog up -- and they do clog up even if you don't leave them in a drawer for years. Just buy new ones, LOL!