Review on Efficient Key Locator: EIRIX Wireless RF Tracker with Remote Control - Find Lost Items Easily with 1 Transmitter and 4 Receivers for Dogs, Cats, Luggage, Wallet, and Keys by Delbert Potter

1. Battery.2. Excellent packing.3. It is easy to follow the user manual written in clear English.4. Have all the necessary accessories you might need, including the battery cover key (round black disc in the picture), ready. Overall it feels like every effort has been put into this product rather than the usual cheap quality of a Chinese mic. So now we're going to see how durable it is and how long a single charge lasts.