The silver medallion is called a “MYSTICAL PENDANT”, or protective shield. It is known as a KAVACH (or yantra or amulet).
Based on classical mystical numbers, the KAVACH strengthens all of the benefic planets in a chart, and reduces the impact of the afflictions caused by the malefic planets.
The remedy is both for the birth chart, and for the daily transit chart.
If a Kavach is purchased you will receive 1 free auspicious time to put on the Kavach. After that, each Muhurta has a change of $40.