The ECS-250-10-37Q-AES-TR from ECS Inc. International is a RF Quartz Crystal with Frequency 25 MHz, Frequency Stability ±50 ppm, Frequency Tolerance ±25 ppm, Load Capacitance 10 pF, Equivalent Series Resistance 100. Tags: Surface Mount. More details for ECS-250-10-37Q-AES-TR can be seen below.