The 501-25351 from Quantic Wenzel (Wenzel Associates, Inc.) is a OCXO with Frequency 1300 MHz, Supply Voltage 15 V, Phase Noise -96 dBm/Hz@100 Hz to -66 dBm/Hz@10 Hz, Phase Noise 1 kHz -126 dBm/Hz, Phase Noise 10 kHz -152 dBm/Hz. Tags: Module with Connectors. More details for 501-25351 can be seen below.