The 501-27584-12 from Quantic Wenzel (Wenzel Associates, Inc.) is a OCXO with Frequency 500 MHz, Supply Voltage 15 V, Phase Noise -115 dBm/Hz@100 Hz to -85 dBm/Hz@10 Hz, Phase Noise 1 kHz -140 dBm/Hz, Phase Noise 10 kHz -152 dBm/Hz. Tags: Module with Connectors. More details for 501-27584-12 can be seen below.