The ECS-250-20-33-DU-TR from ECS Inc. International is a RF Quartz Crystal with Frequency 25 MHz, Frequency Stability ±100 ppm, Frequency Tolerance ±50 ppm, Load Capacitance 20 pF, Equivalent Series Resistance 40. Tags: Surface Mount. More details for ECS-250-20-33-DU-TR can be seen below.