-ʻO ka Pellet apo make i hana ʻia me ka kiʻekiʻe X46Cr13 (stainless steel), a i ʻole 20CrMnTi (alloy steel).
- He kiʻekiʻe ka hua o ka pellet a hoʻopuka i nā pellets kiʻekiʻe.
-ʻO ke apo make he ikaika tensile maikaʻi, corrosion maikaʻi a me ke kūpaʻa hopena.