D/W 211 is a film, skived from virgin PTFE, that has been etched on one side with sodium ammonia (D/W 216), after which a primer has been applied to enhance bonding to elastomers and pressure sensitive adhesives. This surface treatment allows PTFE, which normally exhibits very poor adhesion, to be bonded to other materials. In some applications, sodium ammonia etched materials exhibit somewhat higher strengths than those etched with sodium naphthalene (D/W 212).

Applications for sodium etched PTFE include bonding to elastomers to produce laminated diaphragms, as well as the application of pressure sensitive adhesives in the production of PTFE pressure sensitive tapes. In all of the above applications, the lamination or adhesive application is usually accomplished with a primer that is specific to the material being applied.