D-SERIES (EF) - STANDARD LIQUID TIGHT CONDUIT (IP67). The cotton packed inner core is constructed from a helical formed strip of corrosion resistant steel. A liquid tight PVC jacket is then extruded over the core. D-SERIES (EF) conduit is a fully flexible range with exceptional mechanical strength that is typically found in machining, processing and handling environments. Suited to both liquid-tight applicatiuons and the most demanding environments.