The 501-26943a from Quantic Wenzel (Wenzel Associates, Inc.) is a OCXO with Frequency 200 MHz, Supply Voltage 15 V, Phase Noise -126 dBm/Hz@100 Hz to -96 dBm/Hz@10 Hz, Phase Noise 1 kHz -154 dBm/Hz, Phase Noise 10 kHz -177 dBm/Hz. Tags: Module with Connectors. More details for 501-26943a can be seen below.