The 10202A-50-FC from Thorlabs Inc is a Fiber Optic Coupler with Wavelength 1310 - 1550 nm, Directivity 60 dB, Insertion Loss 3.8 - 3.8 dB, Polarization Dependent Loss 0.15 dB, Operating Temperature -40 to 85 Degree C. More details for 10202A-50-FC can be seen below.