A rechargeable 3.7V lithium-ion battery pack sized for the SinoGnss R500 handheld GNSS data collector, offering roughly 6500mAh (24Wh) of capacity to keep the unit running through a full day of fieldwork. It serves as a spare or replacement cell for R500 units whose factory battery has worn down, and should be charged only with the unit's specified charger and kept away from heat, moisture, or physical damage as noted on the cell's own safety labeling.