Watering bottle cap / Bouchon d'arrosage pour bouteille en plastique

I made this watering cap to save some of my trees as they were suffering because of the heat, and lack of rain this summer.
For some, their leefs went brown and they where close to death...

So, I made a few dozen of these little caps and the trees where saved \o/

This cap fits tightly in water bottles neck (like Evian, Perrier, Cristalline, etc..).
I've use a few 0.5l bottles, a lot of 1.5l ones and some 2l I had left, and for each, it fits and stay.

This cap is designed to drill the