For Watch 38mm. Watch 42mm. Battery Type: Li-ion. Remove the old battery, carefully install the new battery on the battery box, tighten the screws, and then connect the wires of the new battery. Then unscrew the old battery screws one by one, and carefully save each screw.
This battery is ideal for Apple Watch Series 1 owners who desire extended battery life for their 38mm models running on A1578, A1802, or A1553 chips, particularly those using the Iwatch Series 1 companion app.
