The HC-49USSX from ECS Inc. International is a RF Quartz Crystal with Frequency 3.57 to 50 MHz, Frequency Stability ±50 ppm, Frequency Tolerance ±30 ppm, Drive Power Level 500 µW, Load Capacitance 10 to 20 pF. Tags: Thru Hole. More details for HC-49USSX can be seen below.