That is a mantra focused on Goddess Durga in her Chamunda type. Chamunda is a fierce form of Durga, representing the destroyer of evil and protector with the righteous. ॐ ह्रीं ऐं भगवती मतंगेश्वरी श्रीं स्वाहा॥ The Matangi Mantra serves to be a strong Device for spiritual advancement and transformation. https://linkdirectorynet.com/listings12676068/5-simple-statements-about-matangi-mantra-explained