The ECS-73-18-4XEN from ECS Inc. International is a RF Quartz Crystal with Frequency 7.3728 MHz, Frequency Stability ±50 ppm, Frequency Tolerance ±30 ppm, Load Capacitance 18 pF, Equivalent Series Resistance 80. Tags: Thru Hole. More details for ECS-73-18-4XEN can be seen below.