The DFA-1532-041 from Fibertronics Inc. is a Fiber Optic Attenuator with Attenuation 4 dB, Operating Temperature -40 to 75 Degree C, Optical Power w 1 W, Polarization Dependent Loss 0.1 dB, Return Loss 55 - 65 dB. More details for DFA-1532-041 can be seen below.