Nòmalman, Bits egzèsis metal yo se koulè nwa.Metalbitsare ke yo rele tou asye gwo vitès (HSS) oswa twistbits. pafwa, koulè lòj (goldones yo anjeneral kouvri espesyalman pou durability siplemantè).
Bwat metal-perçage yo ka itilize fordrillingplastic ak bwa, men ou pa ta dwe janm itilize woodbitstodrillmetal
