combined with non-rolling cutters other than of leading-portion type

Full Title

Drill bits (specially adapted for deflecting the direction of boring ; with means for collecting substances E21B27/00) > Roller bits (E21B10/26 takes precedence; roller core bits E21B10/06; characterised by wear resisting parts E21B10/50) > combined with non-rolling cutters other than of leading-portion type