This is a fridge magnet with a hole that matches those little 13x4.5mm round magnets, but you can also change that through the f3d file that I have also uploaded.
My printer is pretty toast so I have to print on rafts but it's fine if you don't.
I also have the cap without the emblem uploaded on my profile as a Fusion360 file so you can do whatever you might want with it.
jug_cap.stl | 1.4MB | |
jug_cup.f3d | 21.0KB |