The 501-27990 from Quantic Wenzel (Wenzel Associates, Inc.) is a OCXO with Frequency 100 MHz, Supply Voltage 15 V, Output Power 12 dBm, Phase Noise -142 to -116 dBc/Hz, Phase Noise 1 kHz -141 dBc/Hz. Tags: Thru-Hole. More details for 501-27990 can be seen below.