1.用于測量小孔內徑尺寸 For small holes diameter measurement. 2.帶可換測頭，測量范圍大 Changeable anvils for wide measuring ranges. 3.配φ42mm表圈小型百分表 Equipped with a φ42mm small dial indicator. 4.不銹鋼淬火測頭 Stainless steel hardened contact points.
