The 501-27584-34 from Quantic Wenzel (Wenzel Associates, Inc.) is a OCXO with Frequency 500 MHz, Supply Voltage 12 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: PCB Mount. More details for 501-27584-34 can be seen below.