Nắp vặn thùng nhựa kèm đầu nối vòi Gardena

70 mm and 55 mm plastic barrel bung caps with buttress thread for plastic barrels with closed tops. 
The caps has a 26 mm fine thread for connecting a included gardena hose connector or just a plugg. 

The gardena connector part with 26 mm thread fits in the existing small bung cap in my 208l /55 gallon barrel. 

If you want it water tight two o-rings are required, one standard gardena hose connector o-ring and one 3.1x28OD. It works well without o-rings but will not be water tight. 

I use them as a sealed rain water barrel. With no light nothing will grow inside. 
Look at my other models to make the perfect rain water barrel from a plastic drum!

Update:
Uppdated this model with a small cap (about 55 mm). My plastic barrel has a small and a large cap. I would guess this is standard. 

The gardena hose connector was modified with a larger inner diameter to be less flow restrictive. 

I also added a small M26 plugg that seals of the cap if you don't want to connect a hose.

Update 2:
I've added printable seals/gaskets for the caps which prints in TPU. 

Also I've made socked wrench adapters for these caps in a seperate model, https://www.printables.com/model/1110967-plastic-barrel-cap-socket-wrench-adapters which is needed to tighten the caps enough for use with seals.

Print advice:
Extrusion multiplier: print with a slight overextrusion to avoid “sweating” of the print, I used 1.05
Print material: PETG (PLA will work as well)
No supports needed

seals/gaskets should be printed in TPU and with as small layer height as possible