spiral fluted tap

左螺旋槽丝... ... ) left-spiral flute tap 左螺旋槽丝锥 ) spiral fluted tap 螺旋槽丝锥 ) left-hand thread tap 左旋螺纹丝锥 ...

直角三角... ... "螺旋槽滚子"," spiral fluted roller" "螺旋槽螺丝攻"," spiral fluted tap" "螺旋槽,蜗旋槽"," spiral groove" ...