I have for sale this plug in power meter. It is used (approximately 2 weeks of use), but works great. This unit has saved me a great deal of money in identifying which appliance was using excessive electricity (turned out it was the fridge freezer). It is straightforward to use and can be programmed with your electric cost per unit. 

Battery back up means you can move this device from socket to socket without losing you data.

If you have any questions I will try to answer them for you.

It will be posted next working day after payment, where possible. 

If you wish, you can collect this item and pay cash on collection.

Easily measure the power consumption and cost of your electrical appliances.
Simply plug the meter into the wall and then plug your appliance into the meter. 

With the help of this Power Meter Monitor, You can make certain how much your standby appliances cost, what the power factor is, whether the appliances are really charged, and how long have your appliances been charged.

Features:
- Measures various parameters: power (W), energy (kWh), volts, amps, hertz, power factor and maximum power (W)

Time, days - kWh is vital as this is what your electricity bills are based on!
- Overload Protection Function, overload warning
- Large, clear LCD display for easy reading (screen dimension: 50mm x 43mm).
- Cumulative Kilowatt-Hour Monitor
- Calculates electricity expenses
- Electricity price setting by pressing SET, VALUE, DISPLAY
- Can also set energy Price for night seperately
- Sets electricity price value which ranges 0.000COST/KWH ~9.999COST/KWH
- Low power consumption.

- Power supply: 2*1.5V Button cell backup - allows meter to be moved (and viewed) without losing readings.
- NO Backlight

Specifications:-

When the whole power exceeds the rated power of monitor, the monitor will cut off the
  current and prevent being damaged.
- Operating voltage: 230VAC
- Frequency display: 50/60HZ
- Operating current: max 13A
- Wattage display (Watts) is 0~2900W
- Current range: 0.01A~19.99A
- Resolution: 0.5W
- Indication of frequency: 46-65HZ
- Measurement of consumption: 0.00 to 9999.99 KWh
- Duration of indication: up to 9,999 hours 59 minutes
- 3-pin UK plug
- Dimensions: Length = 135mm; Width = 65mm; Height = 45mm(not inc. pins)
- Functioning indicator