i used it once, what happens...is that when you move a ASIC hashboard in a ASIC like bitmain s17 miner and removes it to get it repaired, transferred or doesn't fix it but tests your hashboard in their miner. When you get hashboard(or miner) back and then its not working because the hashboards have a digital sync codes that identifies each other's miner. SO you need to have at least ONE miner without any issues, plug this device into long enough to copy the digital code, so when the bad hashboard or hashboards that got fixed, gets put back into you miner, then you insert the second hashboard into the device and copy the digital code that you saved in the device to make the miner recognized the repaired hashboard. It helped big time for me. However if the repairs are not done, or incorrectly done, and you copied the saved/pasted digital code in the repaired hashboard, then there are more issues or they were not fixed to begin with. This device is only good for the bitmain ASIC miners. if you have a different brand then the device was not programmed for others, just bitmain miners.