The ECS-270-20-33-CKM-TR from ECS Inc. International is a RF Quartz Crystal with Frequency 27 MHz, Frequency Stability ±10 ppm, Frequency Tolerance ±10 ppm, Load Capacitance 20 pF, Equivalent Series Resistance 40. Tags: Surface Mount. More details for ECS-270-20-33-CKM-TR can be seen below.