All "can" versions have the disadvantage that you first have to pour the antifreeze from the canister into the can, and then from the can into the car.
Too much time?
Well, the fact that I'm writing about this is indeed "donated" time, but not wasted, because I'm also happy when others share information (i.e., take the time) and I just have to read/watch/listen. Currently, it's about the touch adapter for the hands-free system.
The funnel made with HT pipes didn't cost me much time at all: I was already at the hardware store, the basic idea came to me quickly, and I could take the white filter with me to the store to immediately verify the idea. And I can also cut a 40mm HT pipe in a reasonable amount of time.
Another way to look at it is that every hobby is a waste of time, because everyone who doesn't have that hobby proves that it's possible to survive without it.
If there is interest, I can produce the funnels in large quantities

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