MaximalPower 11.10V,4800mAh,Li-ion,Hi-quality Replacement Laptop Battery for Dell Studio XPS 16, Studio XPS 1640, Compatible Part Numbers: This replacement laptop battery can substitute the following part numbers of Dell 312-0814, U011C, W298C 100% Compatible - Will not void your original warranty Tech Rover&trade; Quality product with 30-DAY Worry-Free Return Policy Brand New High output Battery All Tech Rover&trade; branded items carry a 1 year warranty against manufacturer defects.