1.金属罩壳 Metal housing. 2.用于内尺寸、外尺寸、深度尺寸及台阶尺寸测量 Can measure OD,ID,depth and step. 3.读数直观 Easy proof. 4.整体机芯,双向防震 Shock proof. 5.测量范围200mm以上卡尺带微动滚轮 With thumb roller for range 200mm or more.