The 501-25791 from Quantic Wenzel (Wenzel Associates, Inc.) is a OCXO with Frequency 10 - 4000 MHz, Supply Voltage 15 V, Phase Noise -104 dBm/Hz@100 Hz to -86 dBm/Hz@10 Hz, Phase Noise 1 kHz -122 dBm/Hz, Phase Noise 10 kHz -141 dBm/Hz. Tags: Module with Connectors. More details for 501-25791 can be seen below.