The 121 Series from Oscilent is a RF Quartz Crystal with Frequency 38.4 to 76.8 kHz, Frequency Tolerance ±10 or ±20 ppm, Drive Power Level 1.0 ± 0.2 µW, Load Capacitance 12.5 pF, Shunt Capacitance 1.3 to 2.0 pF. Tags: Thru Hole. More details for 121 Series can be seen below.