Having seen the "tame" version of this in some eBay listings (just a box with a switch and speaker terminals), I went on eBay looking for one, and found something much more exciting. This is a lamp tester for use in Chinese factories where they assemble the lamps and then test them to see if they light. This unit also does a fast power test that will beep a warning if the lamp deviates from a preset power range. It's really exciting feature is the auxiliary mains voltage test facility that gives you the option of stuffing wires into speaker connectors or just using flying test probes with full mains voltage on the tips. It makes me wonder how many innocent Chinese factory workers have passed pant-filling amounts of electrical current, or simply had the probes explode on contact with either faulty equipment or random metalwork in the vicinity. Not helped by the unpolarised power connector. I have found the little 8 pin chip data, and it's actually quite an exciting little chip for use in power monitoring applications. It does all the dirty work of measuring current, voltage and phase relationship for accurate power measurement. The processor only has to read it, process the results and then present them on the multiplexed display. Here's the data sheet in English:- https://www.belling.com.cn/media/file_object/bel_product/BL0937/datasheet/BL0937_V1.02_en.pdf Soldering the detached wire back on proved to be a bit tricky, as the wire is definitely not copper and would not take solder well. Note that for obvious reasons this is not suitable for use in factories in the majority of other countries. Test equipment normally has to have safety systems built in to avoid accidental electrical contact. If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:- http://www.bigclive.com/coffee.htm This also keeps the channel independent of YouTube's algorithm quirks, allowing it to be a bit more dangerous and naughty. #ElectronicsCreators