This is a simple screw on cap for a common size of large plastic jug, variously advertised as :
This type of jug is typically used for things like bleach, windshield washer fluid, etc.
Child Safety Warning : The type of jug this cap is made for often contain fluids which are harmful if swallowed, and so are fitted with a child-resistant safety cap. The cap in this print has no safety features, so use it accordingly.
Print in PETG using the 3mf file provided; otherwise :
The OnShape CAD files for this are here :
The author marked this model as their own original creation.