well, i boughtit and can recommend it. But take time to search, there are some that sell separate charges for the battery. The problem is that the n900 will only charge to 1290ma and will then stop and enter maintenance charge. You can then remove it, and plug it in - or charge it while the phone is off. But the hardware will also halt the charge. Someone should write a patch that change the battery capacity - it is not that difficult algorithm. The battery technology has made good progress since the n900 was designed, and 4000ma will soon be available. The charger is software, its described here. My mac has a similar chip fitted in the battery which makes it impossible to recover a deflated battery. So, if you buy the battery you have to buy a separate charger to get it charged above 1280ma... But the phone lasts at least 50% longer than on the old battery.