1. SHE (Standard Hydrogen Electrode) Or NHE (Normal Hydrogen Electrode).
2. Its potential is taken as zero.
3. It consists of a platinum wire sealed into a glass tube carrying a platinum foil, coated with finely divided Pt, at one end. The electrode is dipped in an aqueous acid solution of 1M concentration. Pure hydrogen gas at 1 bar pressure is bubbled through the solution at 298 K.