The HMU-PJAT1K-A05R-MUASA(20) from HIROSE ELECTRIC CO., LTD. is a Fiber Optic Attenuator with Attenuation 5 dB Min., Operating Temperature -25 to 70 Degree C, Optical Power w 200, Return Loss 40 dB Min., Storage Temperature 1620. More details for HMU-PJAT1K-A05R-MUASA(20) can be seen below.