Features: Use mobile phone making call or sending message to this GSM socket to switch on/off the power socket so that to control the electrical appliances It works in any places with GSM signal available Can set up 5 groups of master numbers It can control water heaters, electric motors, electric doors, lights, rice cookers and other appliances Note: 1. Can only control the power supply switched on or off, do not have other functions. 2. In addition to work directly with current electrical appliances, only if other control or button electrical appliances with memory function can use this products. 3. SIM card requirements: Global GSM standard SIM card can be used, currently does not support 3G or CDMA card, please activate the new SIM before insert the device. 4. It is recommended that customers buy an SIM card which is answering free, so it only cause the auto answering messages fee. 5. Incoming Caller ID display must be turned on, make sure that SIM card has sufficient balance in order to call and send text messages. 6. Do not place the GSM switch in the tin trunk or metal enclosed environment. 7. When the signal is weak in some environment, it will make SMS controlled no that ideal and this is normal. Specifications: Voltage: 110V-220V Current: 10A Rated frequency: 50Hz Power: 2200W Plug Type: UK/EU Plug Size: 100x65mm/3.94x2.56" Quantity: 1 Pc Note: Please allow 1-3mm error due to manual measurement. pls make sure you do not mind before you bid Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you! Package Contents: 1 x GSM Switch 1 x User Manual