A chuck pengeboran minangka clamp khusus sing digunakake kanggo nyekel bit puteran;amarga iki, kadhangkala diarani bit holder.Ing latihan, chucks biasane duwe sawetara rahang kanggo ngamanake bit.Ing sawetara model, sampeyan butuh tombol chuck kanggo ngeculake utawa ngencengi chuck, iki diarani chuck keyed.Ing model liyane Nanging, sampeyan ora perlu tombol lan bisa gampang loosen utawa ngencengi Chuck dening tangan, iki disebut keyless chucks.Meh kabeh latihan tanpa kabel dilengkapi karo chuck tanpa kunci.Sanajan nggarap chuck tanpa kunci luwih disenengi amarga gampang, chuck keyed nyedhiyakake keamanan luwih utamane kanggo aplikasi sing luwih abot.