Tanda dumama element juriya ne da sumul karfe tube (carbon karfe tube, titanium tube, bakin karfe tube, jan karfe tube) cike da lantarki dumama waya, da ratar cike da magnesium oxide foda mai kyau thermal conductivity da kuma rufi, sa'an nan ya samu. ta hanyar rage bututu. An sarrafa shi zuwa siffofi daban-daban waɗanda masu amfani ke buƙata. Mafi girman zafin jiki na iya kaiwa 850 ℃.