The Philips 865297 X2,MP2,X3 Battery extender is a extension module. It allows extending the battery capabilities of a X2, MP2,or X3 with a MP series lithium ion battery. The portable monitor slides into the module and connects with a MSL connector. The module has 2 LED lights for battery indication. We see a lot of physical damage to these units due to them always being moved. The physical damage causes charging problem and extension connection problems.