The ECS-51-20-1X from ECS Inc. International is a RF Quartz Crystal with Frequency 5.068 MHz, Frequency Stability ±50 ppm, Frequency Tolerance ±30 ppm, Load Capacitance 20 pF, Equivalent Series Resistance 50. Tags: Thru Hole. More details for ECS-51-20-1X can be seen below.