The RA series dual concentric attenuators furnish high dynamic range and small step size in a single, ruggedized assembly. The outer control knob steps either in 1 dB or 10 dB increments while the inner knob clicks in either 0.1 dB or 1 dB steps, dependi The RA series dual concentric attenuators furnish high dynamic range and small step size in a single, ruggedized assembly. The outer control knob steps either in 1 dB or 10 dB increments while the inner knob clicks in either 0.1 dB or 1