The 2-3953-3X from ARRA Inc. is a RF Variable Attenuator with Frequency 960 MHz to 1.215 GHz, Attenuation Range 3 dB, Attenuation Accuracy ±0.2 dB, Power 5 W, Insertion Loss 0.2 dB. Tags: Module with Connectors, Rotary, Continuously Variable. More details for 2-3953-3X can be seen below.