Nqus khoom nta muaj raws li nram no:
(1) qho cua barrier kev, oxidation kuj, waterproof, ya raws tau.
Kuab (2) txhua yam khoom, siab blasting kev kawm, los tiv thaiv tej qho thiab kuj tsim kua muag.
(3) kub (121 ℃), uas tsis muaj qhov kub thiab txias (-50 ℃), roj, Paul Hong kev kawm zoo.
(4) cov-mob toxic thiab mov, tuaj cov zaub mov, kws ntim tu cev huv.
Zoo (5) sealing kev kawm, yooj, transparency siab.
