The current use throughout the Canary Islands is 220 Volts AC 50Hz and plugs have two round pins as found on the European continent.Travellers from the USA will require a voltage converter, however the better hotels do have provision for 110 Volt appliances like shavers.
Travellers from the UK will require a plug adapter and this is best bought in the UK as they are hard to find in the Canaries. Main sockets require round pin plugs.