Nyob rau hauv cov nqe lus ntawm qhov tseem ceeb hluav taws tsis kam, steel hluav taws qhov rooj yog qhov zoo tshaj plaws nyob rau hauv tib yam khoom, ob qho tib si nyob rau hauv cov nqe lus ntawm lawv tus kheej qauv thiab sab hauv filling. Lub qhov rooj hluav taws kub yog ua los ntawm cov hlau zoo thiab muaj cov khoom siv hluav taws kub. Sab nrauv siv cov tshuaj tua hluav taws xob tam sim no los tiv thaiv kev kub nyhiab, tiv thaiv tub sab nyiag, zoo nkauj thiab ruaj khov.