The FA15T-APC from Thorlabs Inc is a Fiber Optic Attenuator with Attenuation 15 ± 1.0 dB, Operating Temperature -40 to 85 Degree C, Optical Power w 1 W, Polarization Dependent Loss 0.1 dB, Return Loss 60 dB. More details for FA15T-APC can be seen below.