I am familiar with the thermal compounds which fill tiny gaps between a chip and a radiator where the distance between the two is like 0.2mm. I've been messing with this security camera where two of the chips have a blob of gray stuff between them and the aluminum chassis filling a gap of at least 3-4mm. First, I haven't seen this big of a distance gapped with thermal compound. And second, it must be a special type so they are sure it doesn't soften/melt/contract so the gap is no longer filled (it is still pretty soft and pliable after years in there). They also must be dissipating not that much heat with this. Does anyone know what type/brand this type of compound might be?