F999B super wall ear bug

Electric Current Exhaust: 10mA
Battery type: 3.7V lithium-battery
Continuous monitoring for 100hours
Four Audio Choices: A (200MHz) B
(800MHz) C (1200MHz) D (partition bougie monitoring)
Sonde`s sensitivity: -70db, the maximum times of amplifying
the audio: 2000 times
Penetrability: Cement wall, Steel wall, wooden wall, iron wall, glass and air brick
Answering patterns: Headphones, recoding, wireless FM emission