Electrodes, TENS, Misc. - Dura-Stick Premium Electrode, 1.5 x 3.5" Rectangle, stainless steel mesh, blue gel, 40/case : Dura-Stick Premium electrodes have a stainless steel mesh for enhanced conductivity and a blue gel series for those with special skin needs. The electrodes come with re-sealable packaging with fields for patient name, first-use, and number of uses.