... 1.engraving technology support for CNC Engraving Machine 2.Longer life-span than electroplated tool ... 3.faster engraveing speed LONGXIANG stone engraving bits include A, B, C, D, E , F , G series. ... for using our bits and right parameters of engraving machine. D series: Whole alloy stone bits with ... for using our bits and right parameters of engraving machine. ModelShk(mm)AngleOvl(mm)D3-303.173038D3-453 ...