This 600 ohm audio frequency attenuator covers the range 0 dB to 105 dB.

Interestingly, it features a continuously variable attenuation control, in addition to the switched values.

Is is difficult to manufacture a variable potentiometer that maintains a constant input and output impedance whilst providing low values of attenuation. Hence, the first 5 dB of the dial is engraved in red, indicating that these readings are not specified.

Given that, it is a well built instrument and works as intended. But the TF2162 is better!