This firmware is for Eken M013S with version of VT1603_1.5.2.
Firmware Download Link
Instruction for how to flash Eken M013S with this firmware:
Note: you'd better to format ur TF card firstly or the device possibly is not able to recognize the card.
1. unzip this attachment and copy it to ur TF card.
2. plug ur TF card into Eken M013S.
3. press the power button and the device will identify the firmware and begin to flash automatically.
4. after finished, start the device again.