UK 13A Plug to IEC C15 Hot Connector

1.0mm H05RNF Flex -13A Fused UK Plug 
Very similar to the commonplace cable UK To C14 but with a high power C15 connector capable of operating in higher temperatures than the standard C13. Many high power devices now require this connector such as powerful servers in a cabinet. The "notch" prevents use of an under-spec cable. 

Click here for UK to IEC C15 Hot Connector Data Sheet

• Why is this referred to as a "kettle lead"?

  The IEC C15 Connector has been around for decades. Since around 1970 in fact.
  
  A few years before the world's first servers and almost three decades before Tim's first Web-Server it was used for power-hungry devices that got hot, for example; kettles & water urns. Hence it is known as a "Kettle Cable" or as in Australia, a "Jug Plug", which definitely has a better ring to it. So, powerful servers require small but powerful connectors that can operate at high temperatures such as those found in a data centre or server cabinet. The IEC C15 wasn't broke so they didn' fix it.
  
  NB Not to be (but often is) confused with the IEC C13 Connector