be amazing toys rainbow tube science kit. use coloring tablets to make colored water grow clear and colored crystals and make a rainbow test tube using your colored crystals. this kit contains rainbow tablets crystal mix one 6x1 inch test tube and instructions. conforms to astm f963. recommended for ages 4 and up. warning choking hazard small parts. not for children under 3 years. warning this set contains chemicals that may be harmful if misused. use only with adult supervision. imported.