Replace your Garmin RV 660 Battery or Keep an Extra Battery on hand as a backup. This is an Extended Capacity 1100 mAh, Lithium-Ion Battery that offers up even more up time than your original. Works in your Garmin RV 660 GPS. Simple, Easy and Inexpensive! You get a New Battery, a Battery Installation Video, Tools for Battery Installation, AND You also get a full ONE YEAR Money Back Guarantee exclusively when you purchase from us.