Material: Aluminum alloy Color: Silver Internal Diameter: S: 4.57cm / 1.8 inch M: 5.51cm / 2.17 inch L: 6.5cm / 2.56 inch How to Use the Bath Bomb Mold Step 1 Mix the dry ingredients together in a bowl,then mix the liquid ingredients in a separate bowl or jar. Step 2 While constantly stirring the dry ingredients,slowly mix in the wet ingredients,a small spoonful at a time. Step 3: Fill each half of your dome mold with a mix of ingredients until it slightly overflows. Step 4 Press both sides together and use force compact the mixture into the mold,but take care to prevent the mold from cracking. Step 5: Remove excess mixture around the mold. Step 6: Use a metal spoon to tap slightly around the molds. Step7: Gently remove one side of the mold,then gently invert the bath bomb so the uncovered side is facing down,then gently remove the other half of the mold from the top. Ingredients of making a bath bomb 1 cup baking soda 1/2 cup Epsom salts 1/2 cup citric acid 1 tsp. water 2 tsp. essential oil or fragrance oil (avoid minty oils) 3 tsp. olive oil or similar vegetable oil afew drops food coloring (any color)