The JDSU 2014 adapters are designed for instruments with with direct coupling of the test cable to a photo detector. They are also available for various connector standards. A built-in reflection trap within the adapters prevents multiple reflections between the connector's end face and the detector, which would cause incorrect results. This guarantees constant high measurement accuracy regardless of the reflectivity and quality of the surface of the connector. The 2014 universal push-pull adapters (UPP) are available for 2.5 or 1.25 mm connectors.
One 2.5mm UPP adapter fits to all 2.5mm fiber optic connectors as well as the 1.25mm UPP adapter fits to all 1.25mm connectors. So the UPP adapter reduce the numbers of adapters need for power meters.
All 2014 adapters are designed to be used with PC and with APC connectors.