OCXOs and VCOCXOs provide an exceptional frequency stability by heating an SC-cut crystal and further package-internal circuitry to a single temperature, and keeping that temperature stabilized over a range of environmental temperature changes.
As this regulated and stabilized temperature is higher than the highest specified environmental temperature, the abbreviation OCXO stands for Oven Controlled Crystal Oscillator.

These OCXOs and VCOCXOs are an excellent choice if your application requires an extremely stable timing reference with part-per-billion frequency stability. Furthermore, key features are low phase noise, excellent short-term stability, low aging or low drift during holdover.

To achieve a highly disciplined frequency output, JOX254H(V)/ JOX254S(V) uses a 25.4 mm x 25.4 mm metal-can package.
The thermal equilibrium inside the oven of OCXO relies on a larger volume to act as a buffer against the rapid change of outside temperature and wind flux. The extreme stability of +/-0.5ppb over the operating temperature and less than 1E-11 ADEV with 1 sec interval reflects the exceptional capability to ensure that the application can always catch a reliable clock signal. The available frequencies cover up to 100MHz.