double-twist auger bit
/ˈdʌbəlˈɛdʒd ˈɹeɪzə/
n
English · double-twist auger bit中文 · 双螺旋钻头Español · broca salomónica de canal angostoFrançais · mèche hélicoïdale à double torsade
Bedeutung：Bit made up of two opposing twists; it removes debris quickly as the hole is drilled.