The 501-27511-37 from Wenzel Associates is a OCXO with Frequency 80 MHz, Supply Voltage 12 V, Phase Noise -135 dBm/Hz@100 Hz to -105 dBm/Hz@10 Hz, Phase Noise 1 kHz -155 dBm/Hz, Phase Noise 10 kHz -170 dBm/Hz. Tags: Module with Connectors, OCXO. More details for 501-27511-37 can be seen below.