These strings of firecrackers do the trick when you need an extra burst of energy. Many people put these in your Relationship Kua to add a needed spark, or use them to jumpstart your Fame or Prosperity Kuas. They are also used for protection. You may want to check with your Feng Shui consultant for proper installation. These are not explosive; they are facsimiles which are used traditionally in Chinese rituals, ceremonies and cures. Small one measures 18" and the large one measures 60".