Guelph, ON – June 12, 2025 Zentek Ltd. (“Zentek” or the “Company”) (Nasdaq: ZTEK; TSX-V: ZEN), an intellectual property technology development and commercialization company, is pleased to announce new independent test results comparing the viral filtration efficiency (“VFE”) of ZenGUARD™ Enhanced Air Filters against the bacteriophage MS2 compared to equivalent Minimum Efficiency Reporting Value (“MERV”)-rated filters without ZenGUARD™. The testing was performed by the third-party ISO 17025:2017 certified lab LMS Technologies Inc. (“LMS”), which specializes in the testing and certification of filter manufacturers across the world in line with American Society of Heating, Refrigerating and Air-Conditioning Engineers (“ASHRAE”) standards.