The invention relates essentially to an electrical insulation and sealing surround for distributing gases in a high temperature steam electrolyzer of SOEC type or in a fuel cell of SOFC type. According to the invention, some of the functions of sealing, distributing gases and providing electrical insulation between interconnectors are grouped together within one and same component in the form of a surround made of electrically insulating material, the recessed zones of which serve to support the actual sealing gaskets, making them easier to use and to maintain.