Kali Yantra is very powerful and is for the worship of Goddess Kali. This Yantra frees a person from the bad influences of spirits and people. This Yantra also eliminates the harmful effects of misfortunes, sufferings and sorrows in life. The Kali Yantra bestows spiritual power and results in fulfillment of desires, increase in wealth and comforts of life. It also bestows longevity to the person who wears this Yantra on his body.
Kālī - feminine form of kālam ("black, dark coloured"). Kāla means "time" and "black", being first creation before light itself. Kalika Purana depicts as "Adi Shakti" (Fundamental Power) "Para Prakriti", beyond nature. Conveys death, destruction, the consuming aspects of reality - a "forbidden thing". Transformation. Distillation of divine wrath into a goddess of salvation, who rids the sadhaka of ignorance & fear. Kali appears as a symbol of triumph over death.
Kali Yantra. For thousands of years, yantras have been used in the Tantric tradition as visual metaphors for the body of the divine. As expressions of devotion and contemplation, they are similar to Tibetan mandalas in that meditation upon them is tantamount to returning to the primordial fiat of one’s being. Because yantras are comprised of archetypal geometric forms and shapes, they are believed to offer liberation from bondage.