Metal Oxide Varistor / Zinc Oxide Varistor ba mai layi ba ne mai amfani da shi azaman mai amfani da yumbu mai aikin lantarki wanda aka hada shi da zinc oxide. An kira shi varistor ko tunani mai kwakwalwa (MOV), kamar yadda yake da saurin canjin lantarki. Jikin varistor tsari ne na matrix wanda ya ƙunshi ƙwayoyin zinc oxide. Iyakokin hatsi tsakanin barbashi sun yi kama da halaye na lantarki na mahaɗan PN masu haɗuwa. Lokacin da ƙarfin lantarki yayi ƙasa waɗannan iyakokin hatsi suna cikin yanayin ƙarancin ƙarfi kuma idan ƙarfin yayi ƙarfi zasu kasance cikin yanayin lalacewa wanda shine nau'in na'urar da ba layi ba.