The Delfin SkinFibroMeter indentation measuring instrument for tissue hardening measurement consists of a 1.3mm long indenter, a reference plate, and related built-in force sensors. Press the device briefly onto the skin and record the contact pressure. When the reference plate comes into full contact with the skin, the indenter will undergo constant deformation. The skin and underlying subcutaneous tissue resist deformation and determine the hardness value in Newtons (N). The measurement principle is based on the analysis of the biomechanical response of the skin and subcutaneous tissue to external forces. Use 3D computational FE (finite element) analysis to mathematically model the reaction.