The C12000J177 SMD Crystal Resonator with 12MHz ±20ppm HC-49SMD RoHS manufactured by East Crystal are surface mount crystal resonators that have a frequency range of 12MHz, a tolerance of ±20ppm, and are RoHS compliant. They can be used to power a variety of electronic circuits including oscillators, clocks, and signal generators. They are highly stable and reliable components, ideal for use in a wide range of industries.