The mr funnel arrived and has been tested and it does what it says. I poured a glass if water in the funnel and nothing came out the bottom , tipped out then did fuel and it went through then did fuel and water and it let the fuel through but not the water.
Very cleaver , I don't really understand how it works as it has no batteries lol but it does ..
Very simple and cheap bit of kit IMHO and why not as you need a funnel anyway. Will put one in boat and cruiser now as said .
I bought the F1 and it does a jerry in 2 mins the F3 I will try next as it is a little faster.
Jet