Aluminum Flexible Metal Conduit. High Strength Aluminum Alloy Strip. 5/16" is UL Recognized Component. UL Listed in sizes 3/8" to 3". Alflex™ Type RWA is manufactured with a lightweight, high strength aluminum alloy. Metal strip is helically formed into continuously interlocked flexible metal conduit that can withstand impact and crushing forces. This is 3/8in x 100ft Spooled, Flexible Type RWA Conduit conduit.