The G12181-210K from Hamamatsu Photonics is a Photodiode with Wavelength Range 0.9 to 1.85 µm, Capacitance 195 to 500 pF, Dark Current 0.5 to 5 nA, Responsivity/Photosensitivity 0.9 to 1.1 A/W, Active Area Diameter 1 mm. More details for G12181-210K can be seen below.