Remember these from science class? Now you can make your own.

Works with coke bottles
Comes with a choke washer to extend the time of the whirlpool.

May require Teflon tape for a good air tight seal.

check my patreon out- patreon.com/3DPrintingWithDanny

Share your make here or on social media, feel free to tag me as i would love to see how your make turned out!
-thanks