... a variety of environments and conditions, accurate air, bone conduction threshold testing, the automatic fast Speed testing capabilities, ... 10 - 70dBHL. Error less than ± 1%. Output: air conduction headphones, bone conduction headphones, insert earphones, insert masking. Call: built-in call microphone ... ANSI S3.6 1996. Standard configuration: 1.TDH39 bone conduction headset 2.B71 device 3. Two-color pen ...