Eljen PSD Systems
Important Features & How the PDS Works
IMPORTANT FEATURES
Cuspated core prevents rupturing of waterproof membrane.
2-Sided core provides larger total surface area.
Plastic core is flexible to conform to site irregularities.
Unlike many other systems, the fabric is not bonded to the core,
  permitting stretching to help prevent damage during installation.
Fabric is pre-sewn around the core.
Antisiltation fabric protects enclosed drain tube from soil intrusion and clogging.
Installation straps make work safer, surer and easier.

PDS Cutaway