Anyone have any experience with these? I know there is a DTH for other Xiaomi Sensors is this one is dirt cheap.
Lots of different threads about these.
They work well for me.
That’s their PIR motion sensor. The “human body sensor” is just a translation issue. As @bobbles said, several existing threads on it.
Putting price aside, these are excellent zigbee motion sensors having amazingly small footprint, and excellent range. You just need to be willing to deal will the unfriendly (and at times frustrating) pairing process, that is thoroughly discussed around here.