These o-ringed plastic push in bung's are made to fit the inhale/exhale ports on the Meg's head and the kiss quik release fittings.
There is also the oppersite caps that are made to fit over the ends of the hoses for the MEG and KISS, these are made so they slip down inside the fittings protecting the orings
The bung's will keep out water, bugs and stop air flowing through the scrubber bed helping to stop the sorb from drying out, the hose caps protect your orings when the hose are not connected and help track down little leaks on the unit as well as keeping out bugs.
Come in sets of two - mix or match from head to hose bungs