Square karfe: shi ne m, mashaya stock.Bambance daga square tube, m, wanda shi ne bututu.Karfe (karfe): wani abu ne da aka yi da ingots, billets ko karfe ta hanyar sarrafa matsi zuwa siffofi daban-daban, girma da kaddarorin da ake buƙata.Matsakaicin kauri farantin karfe, bakin ciki karfe farantin, lantarki silicon karfe takardar, tsiri karfe, sumul karfe bututu karfe, welded karfe bututu, karfe kayayyakin da sauran iri.