1. Saj zawg zog ntawm pitches.
2. Nws muaj qhov yooj yooj yim, tsis muaj kev thaiv thiab rigidity.
3. Lub teeb yuag thiab zoo caliber sib xws.
4. Zoo yoog raws, rov kho dua thiab hloov tau yooj yim.
5. Zoo corrosion kuj thiab kub kub kuj.
6. Anti nas tom, zoo hnav tsis kam, thiab tiv thaiv cov xov hlau sab hauv los ntawm kev hnav.
7. Muaj zog dabtsi yog khoov tsis kam, tensile khoom thiab lateral siab tsis kam.
8. Mos thiab du, yooj yim rau xov, nruab thiab txoj hauj lwm.