5 Pieces Tornado Tube Bottle Connector,Tornado in A Bottle, Educational Toy Vortex Connector Cyclone Tube for Scientific Experiment and Test, 5 Colors

First and foremost you need to remove the tamper proof ring at the bottom of the cap for it to work leak free!I tried all of them in the package with both two liter and one liter bottles, even one into two liters without issue and no leaking.I’m positive that all these negative reviewers are not getting a tight seal because they can’t thread it in all the way with the plastic ring still on the bottom of the threads. Remove it and it works like a charm! Attached are photos of the piece you need to remove and it working even using a 1L into a 2L bottle (green food coloring just for my toddlers personal preference)For first timers... ***take of the ring on both bottles****, fill one bottle 85 percent full and attach this product...Then attach empty bottle on top of almost full bottle, joining both together....hold the plastic piece in the middle as a handle and flip over so full on top empty on bottom... once you have this just shake it in a circle to get the tornado started. Once it’s started you just turn it over and repeat!Just don’t forget to take off the plastic piece pictured!

this was fun toy for my 7 year old, it does leak a little but for a few bucks it is great

I use one of these to empty shampoo and body wash bottles.

While they do work, the leak all over the place since the threading is too wide to fit snuggly against the bottles.

Does not connect properly to bottles, leaked everywhere, every single one it came with. Going to get a refund. Don’t buy.

As some other reviews have said, make sure you get rid of the plastic ring the cap was connected to so that the connecter fits properly. Once that is done you are ready to create your tornado. Clear bottles will obviously work best. add a little food coloring to make it even easier to see.

I used it for my som schoolProject and it was easy to use

If you cut about 1/2" off of eather end, and are careful about screwing the bottles on, it works. If you try to sighten it down, the threads "pop" off of the bottle. I don't trust it with a 2-liter, so a 20oz bottle it is. Not enough strength to cary the mass of a 1/2 full 2-liter.