Sealant for tubeplate plug

Would someone be able to help me with the type of sealant for the tubeplate plug? Is teflon tape ok or do I use foliac on this one?
Thank's in advance
Phil

Phil:

PTFE is good. Copper grease is also a good idea for plugs: it stops them seizing in place.

Tim

Thank's Tim. Wasn't sure about tape as it's under pressure but should be ok. The copper grease is called coppercoat here but have not seen it for ages and not sure if it's still available. I used to work on steam and we used hemp rope and a product called Dixons sealing compound similar to Foliac paste to seal pipe threads and fittings.
Cheers Phil