What do you put on barrel extensions?

[e z money]

I hear about Aeroshell and green Loctite. I was talking to Noveske customer service and he told me when they assemble rifles, they put Aeroshell on the threads and extensions. When I recently put together an upper, the instructions that came with the parts recommended putting lithium grease on the threads and extension. I'm guessing Aeroshell is lithium grease. I wanted to see what type of lithium grease I could find locally. Thought I would share with you what I found at the auto parts store. I think it's good stuff. I put it on the barrel threads and extension. It's a Lucas Oil product Red "N" Tacky lithium based grease. I think it has a higher temperature rating than Aeroshell. I did not get the spray on type, seems like it might not be as good. What works best? I'm just wondering what you guys use, and your opinions and if anyone uses this product of rifles.