Many interventionists are infatuated by the recent resurgence of the coilwire design with the Super Arrow-Flex® sheath (Teleflex, Inc., NC, United States of America). This exclusive sheath is a highly flexible, durable, conduit intended for use in diagnostic and interventional procedures with several advantages and maximum effectiveness in challenging cases. We report failure to easily advance memory shape occluders through Super Arrow-Flex® sheaths larger than the recommended implant French size. We detail the technical reasons behind this non-previously reported drawback and describe benchside tests as possible solutions.