Putting duraline on the raspberry trellises May 15, 2015 by Marilyn OdnealWe use a 12.5 gauge monofilament line – Duraline – for the catch wires on the raspberry trellis. We use gripples to connect the lines and tighten them. Randy Stout and Jeremy Emery install the Duraline. Photo by Jennifer Morganthaler. The line is tightened with a gripple and a gripple tool. Photo by Jennifer Morganthaler. Here is a close-up of the metal gripple holding the Duraline together. Photo by Jennifer Morganthaler.