The 501-28227 from Quantic Wenzel (Wenzel Associates, Inc.) is a OCXO with Frequency 10 MHz, Supply Voltage 15 V, Phase Noise -160 dBm/Hz@100 Hz to -143 dBm/Hz@10 Hz, Phase Noise 1 kHz -168 dBm/Hz, Phase Noise 10 kHz -172 dBm/Hz. Tags: Module with Connectors. More details for 501-28227 can be seen below.