Lip Materials:
* NBR Nitrile rubber
* FKM fluororubber / fluoroelastomer
* Silicone rubber
* Nylon or polyamide
* Polychloroprene
* Polyetheretherkeytone
* ACM / Polyacrylate rubber
* PTFE / Polytetrafluoroethylene
* Polyurethane
* Stainless steel
* Felt
* Leather