Sib npaug thiab tsis sib npaug yog ob hom loj ntawm lub kaum sab xis steel:
Lawv yog cov feem ntau hom steel seem thiab tuaj yeem ua rau ntau yam specs thiab txiav rau txhua qhov loj, ua rau lawv muaj ntau yam. Lawv qhov loj me yog sawv cev los ntawm sab A x sab B x thickness.
