The ECS-160-18-33-AEL-TR from ECS Inc. International is a RF Quartz Crystal with Frequency 16 MHz, Frequency Stability ±50 ppm, Frequency Tolerance ±25 ppm, Load Capacitance 18 pF, Equivalent Series Resistance 80. Tags: Surface Mount. More details for ECS-160-18-33-AEL-TR can be seen below.