The 501-28039 from Quantic Wenzel (Wenzel Associates, Inc.) is a TCXO with Frequency 50 MHz, Supply Voltage 10 V, Output Power 7 dBm, Phase Noise -163 to -115 dBc/Hz, Phase Noise 1 kHz -135 dBc/Hz. Tags: Through-hole. More details for 501-28039 can be seen below.