The ECS-250-12-30BQ-AEN-TR from ECS Inc. International is a RF Quartz Crystal with Frequency 25 MHz, Frequency Stability ±50 ppm, Frequency Tolerance ±25 ppm, Load Capacitance 12 pF, Equivalent Series Resistance 30. Tags: Surface Mount. More details for ECS-250-12-30BQ-AEN-TR can be seen below.