Open up the barrel

One end of the plate unscrews the main barrel plug, whereas the other takes care of the little vent plug. What could be simpler?

For those farmers who buy their oil in 205-litre drums, here’s a dedicated tool that’s able to whip out barrel plugs in a matter of just seconds.
Check the diameter of your barrel plug and then weld a plate of the correct width to a 40cm long handle. At one end of the plate, cut out a 2cm wide nose — the end for unscrewing the barrel’s smaller vent plug — leaving the other uncut end to take care of the main filler plug.