Callaway FS171 Battery with Universal Charger (100/240V) - Replacement Callaway uPro Golf GPS Battery (800mAh, 3.7V, Lithium-Ion) Replacement Callaway FS171 Battery and Charger Universal Charger features adjustable slider to charge different lithium-ion batteries (3.6V/3.7V). 100-240V autosensing for world wide use. Lifetime Warranty Callaway uPro Battery Specs - Capacity: 800mAh, Voltage: 3.7V, Upstart Battery Brand On Sale for a Limited Time!