It tells you on the PCB that the OEM is UNI-T. The meter is the UT139B which sells for about $40.00 direct from China. Same as 139C, but with a lesser 4,000 count and no temperature function. It should be quite safe on mains.
Yes, it's a rebranded UT139B 4000 count meter. The better one would be UT139C 6000 count more accurate and more features like measuring caps to 100k uf. NCV ( non contact ac voltage detection like
checking for ac wiring hidden in walls ...hopefully it's sensitive enough) and most important true rms for ac voltage which is also on the B version.
Overall quite decent meter protection as you can see 2 ceramic fuses with PTC resistors for over voltage and current protection but that does not mean you can anyhow abuse it like switching to resistance rage while the probes are connected to high voltage and current source like your wall ac sockets. Yeah you got your money's worth.
PS: Repair note, on my 139C version, 2 smt caps on the left side developed high esr problem resulting in higher resistance when probes are shorted for resistance range. I replaced these with through hole e-caps as I could not bother getting smt types. After replacement "zeroing" resulted in the lowest ohm reading of 0.3 ohm which is back to normal.