Neodymium Magnetic Base with a pull force of 110lbs</br>Gasket Sealed Waterproof Case</br>Add Extended Months of Tracking Power</br>Perfect Fit for the GL200, GL300, Spark Nano 3.0</br></br>Product Description</br></br>6 Month Extended Battery Pack with Magnetic Waterproof Case Perfect fit for the GL200, GL300, Spark Nano 3.0 Not Compatible with the Spark Nano 4.0 and 5.0 GPS Tracker Not Included</br><br/>http://www.amazon.com/gp/product/B016GTDBQI