Petrol tank

What,s the best thing to sit the petrol tank on. Rubber, foam or felt? I can't remember what was under the tank when I took it out 9 years ago!

 

I think I put some cork under the last one I did, that had nothing there...

 

Im going to use closed celled foam

 

originally it was a fibrous strip... something a bit like horse hair and something!!

 

Thanks for the replies gents. I might try closed cell foam...about 2-3mm thick.