Connect this tornado tube connector to two plastic pop bottles (fill one bottle 3/4 full with water). Stand the bottle so the water is on the top and give the bottles a swirl. Watch as the tornado (vortex) forms inside. You don’t always have to use water with your Tornado Tube Connectors. Use sand, salt, glitter, colored sand, colored salt, liquid soap…instead of the water. Use these tornado tube connectors to create a mini timer with the mini bottles and a dry substance (glitter, salt, sand….). Mini bottles are sold separately (see item #MB15 for 15 mini bottles or item #MB01 for a single mini bottle). Bottles not included.