The Driftmaster 1 Round Rail Rod-Holder Base is constructed of plated steel with a durable plastic coating to protect rods. Bases are crafted from aluminum. Stainless steel hardware included on bases Left thread model is for trolling off the port side of your boat. Left-thread bases use hex nuts. 1 Round Rail Base. threads. Cancer and Reproductive Harm- www.P65Warnings.ca.gov. Type: Rod Holder.