Akwụkwọ ntuziaka griiz ụdị akwụkwọ ntuziaka grese bụ plancing ụdị lunger, ma ọ bụ nwere ike kesara mmanu mmanu, ma ọ bụ nke na-ekesa ya site na onye na-ekesa na-arụgide ya (slr) PDI) na onye nkesa na-ekesa (PRG). Ọ dị mma maka lubrication nke obere na ndị na-ajụkarị -
