Combination switched sockets including 250V and 500V as below: 500V combination switched sockets All 500V switched sockets rated 32A and above have an internal interlocking feature(plugs can not be withdrawn or inserted when the switch is in the ON position. This feature is also availbale for 16A AND 20A upon request. Optional keylocking OFF facility(quote'CVK' when ordering keylock type, e. G. Cat no. 56CVK432). 110-250V socket outlets The 56 series includes an extensive range of one piece combination switched sockets. Optional keylocking OFF facility(quote'CVK' when ordering keylock type, e. G. Cat. No. 56CVK310). For NEON indicator option add 'N' after catalogue number.