I use 5 gallon "utility cans" with a big screw on cap. Put one of these through the treads threads in the center. Use the valve to regulate volume of flow or inhibit until the nozzle is in the filler cap.
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Yes, many trucks in government service are not subject to the government's regulations for us little folk. But I was referring how government regulators writing regs for gas cans do not use gas cans themselves. Don't mow lawns. But feel their superior intellectual powers, having contemplated the...
That is the "flame barrier" which bankrupted Blitz. Lawyers claimed a simple screen would prevent flames running inside the nozzle from reaching the inside of the gas tank.
Plenty of evidence to the contrary, but good enough to convince ignorant jurys that Blitz was negligent for exploding...