If you on your computer all the time,.. then you have to swap out the rechargeable battery at least once a day. Waste a lot of time,.. I swich back to my original Microsoft mouse and that used 2 AA batteries and it last more then one month.Don't buy, you will get tried of changing battery everyday!!TRUST ME,.. YOU WILL GET TRIED OF PRESSING THE BATTERY RELEASE BUTTON ON THE CHARGER BASE,..AND IT GET STUCK HALF THE TIME.AND THIS LASER MOUSE WORK JUST LIKE ANY OPTICAL ONE,.. DON'T THINK IF YOU GETTING A LASER IS BETTER,..ITS SURE NOT,.. I CAN'T TELL THE DIFFERENT.FINAL NOTE,..BATTERY LIFE STINK,,,LASER IS NO BETTER THEN OPTICAL