This Trap can be mounted on Coke bottle or any soda bottle with same thread.
Thanks to its funnel shape flies or wasp attracted by smell will go inside the bottle but they will not find the way out...so basically they will die.
You just need to put inside a sardine fish (better if you cut in 2-3 pieces) and fill 3/4 with water. Hang it in your garden at approx 1,5 meter from the floor, not too closed to your house since this will attract flies.
After 3-4 days (fish needs to start decomposition) it will attract flies.
The more flies will die the better it will work, so when it will be full you can just empty half of it and add water (fish will no longer be necessary)
In this case do not put fish but 1/2 water - 1/2 beer - eventually some some sugar spoons (beer is the most important part)
Of course fill for 3/4 of the volume.
Wasp attraction will start immediately so this could be a good solution fot excursions, camping etc.
Keep original bottle cap. Once full you can use to close bottle and put in the bin...or you can just empty and reuse.
Thanks to Alexander Purikov for cup thread.
15/03/2015 - improved hole for putting hanging string with a slide.
I suggest yellow colour as flies loves yellow.
I printed 0,2 layer