This Bird 4275-100 Thruline Variable RF Signal Sampler, is used and in excellent condition.
It covers 20 to 1000 MHz. It will mount to any Bird 43 wattmeter as shown in the pictures.
4275-100 Thruline RF Signal Sampler, is a stand alone wide-range THRULINE RF coupling probe for spectrum analysis, RF signal observation on a scope, or frequency counting and control.
It features a very low VSWR over a broad frequency and attenuation range. Insertion loss is a negligible 0.1 dB. Once adjusted, the setting can be locked in place. The main power connectors are Bird QC type N(M) to N(F) standard, others available. I also have the Bird QC connectors and adapters available.