Hello All
If you are looking for grommets for cables etc passing through GRP then Wiska FD range is quite good. FLIP cable grommets, FD - Cable entries - WISKA These are available online and from most decent electrical wholesalers. The 16mm grommet can cope with panel thickness between 1 and 4mm so good for Ally panels too. They are IP66/7 rated so probably better than most of the other grommets I have seen. No connection, just happy with them.