The delivery was prompt. The installation of the batteries was not smooth. The battery kept falling out of the housing. The latch fits not optimal. With a little pressure, we went yet. Function properly. Despite the slight difficulty I forgive 4 points. The service life of the battery has increased from 1.5 hours to almost 4 hours, according to the display Note Book. That's a good value. Price / performance optimal. Due to the increased battery results in a slight inclination of the Note Book. Is very pleasant.