MOTM

I've ordered a few boards and panels (OK, I admit it: I ordered almost
everything), and I'm planning the parts shopping. In the BOM that Paul
kindly posted, some of the caps are identified as "yellow box" caps. 
Any idea who makes these? And what are they, anyway - ceramic,
polyester, what?

Thansk for the help.
mrmike

"MOTM - It's not just a hobby, it's an addiction!"