Review on Upgraded Fuel Gas Can Vent Caps With Lanyard Attachment - Improve Gas Can And Tank Flow - Kit Of 12 For Quick Dispensing From Water Jugs And Fuel Tanks by Jason Przystup

These are far more functional than other types of vents installed after throwing out your government mandated spouts. They are a bit tricky to install and you really need to do it on a can which is empty. Not so much for a potential fire, but because you cannot avoid dropping plastic fragments in the can when drilling the hole. They work well, but be sure to find a flat spot so the o-rings can seal.