The researchers studied how adding borosilicate frit to ZnO varistors affects their structure and electrical behavior. They used small ZnO particles and different amounts of borosilicate frit to make the varistors. The frit helped the varistors become denser and grow larger grains, even with a small amount added. X-ray analysis showed a new compound formed when too much frit was added. The electrical properties changed with frit concentration, with breakdown voltage and resistivity decreasing as more frit was added. This shows that adding borosilicate frit can control the structure and breakdown voltage of ZnO varistors made from small ZnO particles.