The 501-27182a from Quantic Wenzel (Wenzel Associates, Inc.) is a OCXO with Frequency 1280 MHz, Supply Voltage 15 V, Phase Noise -110 dBm/Hz@100 Hz to -80 dBm/Hz@10 Hz, Phase Noise 1 kHz -137 dBm/Hz, Phase Noise 10 kHz -160 dBm/Hz. Tags: Module with Connectors. More details for 501-27182a can be seen below.