The Brennenstuhl Energy Cost Measurement Device has a programmable display that can be set to show whatever energy consumption information the user needs.
It can be set to display the actual current consumption, the actual current costs, the total current consumption and the total current costs.
It also displays measured time in hours and minutes and has two adjustable electricity tariff settings (day and night).
Comes with 2 batteries (LR44).
Very easy to use, just plug it into a UK/Ireland 3 pin power socket and plug the appliance you wish to measure the power consumption of into the EM240.