Expanding foam, good call to keep insects out

Certainly works , I’ve found they crawl towards the light up inside the spigot tube, then once in the gear aperture they’re into the bowl where they fall dead during the night, and there’s nothing worse than a bowl full of dead things!

They must be drawn to the heat of the lamp and gear? At least this also keeps the ballast from going rusty, a lot of these lanterns with low IP rated gear areas end up quite manky inside after some time, the Parmar ballasts in the Sapphire 1's rusted terribly whereas they stay looking brand new in the well sealed Arcs!

I’ve still got the actual original ballast this came with , it is indeed a bit rusty, another reason I like my ballasts remote , the one in the Arc80 isn’t so bad, as I know the Arc is well sealed!