ERL Online

Best for micro-controller based projects done in school and colleges. Works best with any kind of micro-controllers.
Standard frequency crystals - use these crystals to provide a clock input to your microprocessor.
Rated at 20pF capacitance and +/- 50ppm stability.
Provide clock pulses of 16 Mhz frequency. It can be used as UART clock.
Allows integer division to common baud rates (96×115200 baud or 96×96×1,200 baud).
A common clock for AVR microcontroller It uses the mechanical resonance of a vibrating crystal of piezoelectric material to create an electrical signal with a very precise frequency