I need for my 6 or 7 year old Asus X51 notebook a new battery because the old stores only half of the performance. According BatterieBar can store up to 48400 mAh this rechargeable battery 45881 mAh there are currently, ie 5.2% reduction. At a purchase price of EUR 22.59 with postage means the full 5 stars and a buy recommendation.