The HC-49/U-S4000000AHKB is a 4MHz quartz crystal manufactured by Citizen. This crystal is a crucial component in electronic circuits, providing a stable and accurate frequency reference. Encased in a through-hole HC-49/U package, it offers reliable performance and easy integration into various designs. As an authorized distributor of Citizen components, Supreme Components International guarantees the authenticity and quality of this crystal. It is suitable for applications such as microcontrollers, real-time clocks, communication equipment, and signal processing circuits. The HC-49/U package ensures robust mechanical stability and ease of soldering. Choose this crystal for dependable frequency control in your electronic projects.