The ECS-120-12-33QZ-ADS-TR from ECS Inc. International is a RF Quartz Crystal with Frequency 12 MHz, Frequency Stability ±100 ppm, Frequency Tolerance ±25 ppm, Load Capacitance 12 pF, Equivalent Series Resistance 120. Tags: Surface Mount. More details for ECS-120-12-33QZ-ADS-TR can be seen below.