Horsetail whisk is a tool to repel insects. Animal hair, cotton, linen and the like is tied to the handle, which becomes a horsetail whisk, having the same function with dust tail and being of various shapes. The horsetail whisk is usually used to drive away mosquitoes in India. Monastics of Chan school upheld the horsetail whisk becoming fashionable or took it as a solemn Buddhist instrument since the Tang Dynasty. Abbot or acting abbot gave a dharma teaching to the public, which is called taking the whisk. The horsetail whisk is also one of teaching aids that the patriarch of Chan Buddhism used most.