He shared his concerns at the Black Hat security conference.[71] Radcliff fears that the devices are vulnerable and has found that a lethal attack is possible against those with insulin pumps and glucose monitors. Some medical device makers downplay the threat from such attacks and argue that the demonstrated attacks have been performed by skilled security researchers and are unlikely to occur in the real world. At the same time, other makers have asked software security experts to investigate the safety of their devices.[72] As recently as June 2011, security experts showed that by using readily available hardware and a user manual, a scientist could both tap into the information on the system of a wireless insulin pump in combination with a glucose monitor.