What goes between the transister and the metal finn??

[TerryD]

OK This is another question.  I have my new transister on the Crate.  I could see that there was some thin piece of something between the transister and the metal fin piece on the back of the amp. To make something like that, I cut a piece of the electrostatic plastic that the transister came in and gunked it up with waterproof caulk....think that will be ok as a film between the transister and the metal finn??  I put some plastic wire coats on the two prongs so they don't get grounded.  So far works good. 

I also have to get the thermalloy now.  They did not have them where I cot the transister/in stock.  I can get one off the net for .80 cents and $5.00 to ship...got any other ideas?

[sluckey]

You need a TO-3 mica insulator.

[TerryD]

excellent.  Thanks. That should do it.