Simple one-way valve, no moving parts (Tesla valve)

thingiverse

A Tesla Valve is a tube with no moving parts that restricts fluid flow in one of two directions. For instance: blowing into one end is effortless, while an incredible amount of force is required when blowing from the other end. Print it out and see for yourself - no supports, rafts, or filament changes needed. It prints as-is on almost any printer. Note that this build comes in two halves; to complete the valve, one half must be coated with glue on the channel side (don't get glue in the channels) and flipped over on top of the other side. Make sure the channels on the two halves line up before gluing them together. If you enjoyed building it or thought it was cool, don't forget to like it and post a make! Also, we appreciate your design feedback - thanks!