Ojiji ngwa:
A na-eji ya anwale iguzogide okpomọkụ na iguzogide mmiri nke ákwà, uwe, ihe ndina, wdg, gụnyere njikọta ákwà nwere ọtụtụ oyi akwa.
Zute ọkọlọtọ ahụ:
GBT11048, ISO11092 (E), ASTM F1868, GB/T38473 na ụkpụrụ ndị ọzọ.
