The Model LA100 is a 40dB attenuator that is recommended for use with the AR RF/Microwave Instrumentation S, ST and T series models and other amplifiers with an N type output connector operating in the same frequency and power range. The attenuated output provides a means of monitoring the signal at an acceptable level for a power meter or oscilloscope and permits use of a detector for RF leveling. A test data sheet is provided with the LA100 to indicate attenuation over the frequency range.