The 49SAC27000202040 with DIP Crystal Resonators HC-49S RoHS is an electronic part manufactured by JGHC. It is a small package surface mount electronic component, specifically a type of quartz crystal resonator. It is composed of a ceramic base, a sealed, hermetically-encapsulated quartz crystal, two series-connected electrodes, and two bonded wires lead terminals. It is RoHS compliant, meaning it does not contain any hazardous materials, and can operate in a wide temperature range. This component is used in many electronic applications, including timing circuits, clock generation, and frequency control.