The ECS-500-8-47B-CWY-TR from ECS Inc. International is a RF Quartz Crystal with Frequency 50 MHz, Frequency Stability ±15 ppm, Frequency Tolerance ±10 ppm, Load Capacitance 8 pF, Equivalent Series Resistance 50. Tags: Surface Mount. More details for ECS-500-8-47B-CWY-TR can be seen below.