I keep going out shopping, and think i want to get some hose that will fit tightly into the grommet that i usually have my airlock in. I know the hole the grommet is in is 1/2", but don't know what the interior hole size to the grommet is... I keep forgetting to measure.
what exteriror dimension of hose will fit this grommet tightly?
what exteriror dimension of hose will fit this grommet tightly?