I have several Yihua soldering products and am impressed with their value for money. They are reliable and accurate. I use them with Hakko materials, usually for minor soldering jobs. I was worried it might be fake; There are millions of counterfeit 858ds out there with grounding, polarity, and fuse issues. First, it came with a Yihua authenticity QR code confirming it was positive. Second, I checked the floor. The SS heater nozzle and case were firmly connected to the center round ground pin of the AC power plug. Third, I checked the polarity of the AC plug. The hot and neutral wires have been properly connected. Fourth, I checked the fuse. It was hot connected to AC as it should be. So this is a real Yihua 858d. In terms of performance, it heats up 15% slightly higher than the specified temperature. It's not a Hakko, but considering the latter costs $2,000, it's a good deal. Just avoid those fake 858ds!