What type of grease/sealer should I use for my slip on exhaust?

[AryanWinters]

I've read a few forums and heard it is best to apply grease on to the inner pipe before putting a slip on exhaust and clamping it down.

I'm installing a Werkes GP Slip On for the 2016 KTM RC 390 and was wondering if anyone knows if KTM recommends a particular type of grease or application to use with slip ons