Abstract: The tubular water device comprises an inner conduit, an outer conduit, substantially surrounding said inner conduit, an electro-resistive heating element, disposed adjacently to an outer surface of said inner conduit for transferring thermal energy to fluid contained in inner chamber and in outer chamber; a continuous metal sheath, substantially covering and sealing said electro-resistive heating element, forming monolithic tight heating tube. As heating material a crystalline metal foil is used. It is shown different applications.