This product is a sheet-like ultra-fine plugging material made from natural mica ore, featuring good toughness and temperature stability. By overlapping and stacking the sheet structure, it rapidly seals micro-fractures and pores in the formation, effectively reducing drilling fluid loss, reinforcing the wellbore to prevent collapse and block shedding, and also improving the smoothness of the mud cake while reducing drill wear. It is chemically stable and compatible with various drilling fluid systems, commonly used for leak prevention and wellbore protection in easily collapsing or fractured formations.