The FoMS(Fiberoptic Manual Switch) has been precisely designed for variety of MT/MPO based component measurement.
For instance, the FoMS helps the single core based optic power meter measure QSFP+ SR4 and QSFP28 SR4. MPO based components keep widening its variety.
In case of SFP-DD and QSFP+ SR, however both utilize the same MPO 12 fiber connector, the polarity type is different so the conventional MPO power meter is not able to measure both types.
The FoMS offer the solutions for such complicated MPO based component measurement.