| Hi Alan
Go with silicone grease from a dive shop its inert to almost everything out there. It lubricity is not perfect but it wont destroy any of the plastics your going to come across on a day to day basis.
I restore vintage fountain pens for a hobby and its the only grease thats safe on all pen materials.
PTFE dry lube is still in a carrier most likely iso propane or butane based if in a spray can. PTFE on its own is reasonably inert but i wouldnt want it on styrene.
kevin |