Some of you may fear them, but children seem to be intrigued by them! Spiders can provoke so many different emotions and this award-winning large scale spider is sure to do just that! Your Salt Water Fuel Cell Spider Kit contains everything you need to make a realistic (although quite large) robotic spider that is powered purely by water with a little added salt. Once you have completed and activated your spider, it will scurry around on your floor, it`s legs moving up and down as it runs. Watch him scurry for 7-8 minutes before re-fueling! Argh! Your spider is powered by a special fuel cell (that you build yourself) to create power through a chemical reaction between metal and saline water. You`ll find your kit to be fun and educational as you learn about new forms of clean energy and the anatomy of a spider! Be amazed at how your spider will come alive and move along in a VERY frightening manner! All materials used are environmentally safe and clean, no toxic substances or chemicals used. What a fantastic gift for a budding scientist or arachnoidoligist! It is not suitable for children under 3 years old and is recommended for age 8 and above. Size of spider: 8cm x 6cm x 3cm.