Inconsutilem chalybem fistula toto ferro rotundo perforata est, et fistula ferrea in superficie chalybea sine ferro inconsutilem fistulam dicitur. Secundum methodum productionis, fistula inconsutilem chalybem dividi potest in fistulam ferream calido-volutam inconsutilem, fistulam ferream frigido-volutam inconsutilem, fistulam ferream strictam inconsutilem, fistulam ferream inconsutilem, extrusam fistulam ferream inconsutilem, fistula jacking, etc.