Specifications: Capacity: 2200 / 4400mAh Chemistry: Li-ion Voltage: 14.4V Cell: 4 / 8 cell Compatible Models: HP Probook 4210S HP Probook 4310S HP ProBook 4311 HP Probook 4311S Please carefully check your battery's Compatible Model & battery picture to ensure compatibility with your Laptop. What's in the box 1 x A