Ael crystals hc 49u quartz crystal resonators through hole ael x8m000000l129 a 8000000mhz crystal resonator with a tolerance of 10ppm in a hc 49u style holder that is suitable for a wide range of frequency control applications and serves as direct replacement for existing designs ael x8m000000l129 80mhz 10ppm hc49u quartz crystal resonator