The NJR2837U from Nisshinbo Micro Devices Inc. is a Low Noise Block with RF/Input Frequency 10.95 to 11.70GHz, Output Frequency 950 MHz to 1.7 GHz, LO Frequency 10 GHz, Gain 55 to 60 dB, LO Frequency Stability +/- 1 ppm. More details for NJR2837U can be seen below.