Little floating boiling things - (Aug/02/2007 )

Ok, I know this is silly, but...
What is the name in English of these little floating things for water bath you keep the samples in, to boil something?
Just don't ask why...
I am sure somebody knows.

I think they can be called ''floats'' as a noun.

Oh, thank you. I found it under "floating racks".
In the protocols it always says "boil the samples", I use one thingie, started to run much more samples and wanted to buy more.
I know so many difficult words and this one was simply too obvious...