Hello! Wireless monitoring also has a power supply. It must be charged and does not need to be plugged in. It is similar to our cell phones which have batteries inside.
However, the wireless monitoring probes currently on the market are uneven, with different capacities and sizes, as well as different sizes.
You can choose according to your own needs. For discreet monitoring, you can choose something smaller, but the power capacity is not too large and the battery life is limited.
If you don't need hidden monitoring, you can choose the direct plug-in type, so you don't have to worry about battery life.