[sdiy] What are these Capacitor's type ???

[Jean-Pierre Desrochers]

Can anybody tell what type of capacitors
are these in the picture here:
http://www.arcenson.com/public/Capacitors.jpg

They are manufactured by Sangamo but can't say more.

Would they be paper capacitors type ?
I know they are vintage ones so would they need to be replaced.
Their shell looks like plastic so they should
be humidity proof.. still reliable ??
They were part of a vintage RF Generator.