1. It's high Amp item, and the device needs certified and professional electrician for wiring._x000D_ 2.The frequency of the wireless router is 2.4GHz._x000D_ 3. The meter requires the measured device must have neutral wire. otherwise it can't measure the device's voltage, current, and power._x000D_ _x000D_ When you install the CT , please note the CT's direction, make sure all 3 CT with the same direction._x000D_ With External Antenna for Strong and Stable Signal._x000D_ Type: 120A_x000D_ Material: Plastic_x000D_ colour: White + Black_x000D_ _x000D_ Package Contents:_x000D_ 1 x KWH Meter_x000D_ 1 x Antenna_x000D_ _x000D_ Only the above package content, other products are not included._x000D_ Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm. _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_ _x000D_