The 501-27515-04 from Quantic Wenzel (Wenzel Associates, Inc.) is a OCXO with Frequency 200 MHz, Supply Voltage 15 V, Phase Noise -113 dBm/Hz@100 Hz to -83 dBm/Hz@10 Hz, Phase Noise 1 kHz -143 dBm/Hz, Phase Noise 10 kHz -158 dBm/Hz. Tags: PCB Mount. More details for 501-27515-04 can be seen below.