What use small radiator at beginning?

[El Sancho]

New KSP version, I haven't played for a few months, so I decided to start over. And in doing so I ran across something I have long wondered about, so I thought to myself "hey, this time I'll go ask!". Yes, I did search the forums for existing answers first.

I am at just the third step of tech tree, two up from "Start". Bottom icon of the three, little parachute icon, called "Survivability". It includes the Small Radiator part. What use would one have for a Small Radiator at that tech level? It was my understanding that Radiators and such were only for cooling things like drills and ore processors, which come along much later in the tech tree. What am I missing?

[bewing]

Sometimes they can also help a little bit on reentry, to reduce max heating by a little.

 

[El Sancho]

OK. Thank you for the reply.