The 1: MM_COUPLER_2x2 from Diamond SA is a Fiber Optic Coupler with Wavelength 1310 - 1550 nm, Directivity 60 dB, Insertion Loss 0.2 - 23.1 dB, Return Loss 60 dB, Polarization Dependent Loss typical 0.05 dB. More details for 1: MM_COUPLER_2x2 can be seen below.