•To allow for the hundreds of different trailer configurations regardless of manufacturer, these curtains have been designed to adjust on their height prior to installation in the trailer.  All of this adjustment occurs at the top of the curtain so that the E-clips and their horizontal cargo straps are never affected.  The Load Restraint System Specifications of the US Postal Service require that your E-Tracks are installed 28.5” and 62.5” on center off the floor and when viewing the erect curtain you will note that these distances are where our E-clip assemblies are located.  The curtain is made secure across the width of the trailer by first inserting the driver’s side E-clips into the 2 respective tracks, then inserting the curbside E-clips, then ratcheting tight.  The curtain is then made tamper evident by placing USPS tamper evident seals through both ratchet handles and the brass grommets provided in the cargo straps the handles are attached to.