The above monthly star charts show the position of the three common potent stars 2 Black 二黑 , 3 Jade 三碧 , and 5 Yellow 五黃.
Star 2 use a strand of 6 ancient Chinese Emperors metal coins.
Star 3 use red color or a table lamp.
Star 5 use a 6 rod metal wind-chime or metal cure.
Obviously in today’s modern market there are many alternatives but make sure they are of equivalent functions. Do beware of opportunists.