MTP/MPO loopback modules are used widely within testing environment. Devices allow verification and testing of transceivers featuring MTP interface - 40G BASE-SR4/CSR4 QSFP+ devices. MTP/MPO fibre optic loopbacks are built to link Transmitter (TX) and Receivers (RX) positions of MTP/MPO transceivers interfaces. MTP/MPO loopback modules can facilitate and speed up IL testing of optical networks segments by connecting them to MTP/MPO fibre trunks/patch leads.

In majority of cases, if two MPO connectors are mounted on a patch panel and you want to loop them from the front of the patch panel, you will need female to female loop back MPO Polarity A.

If you are testing a Trunk cable, (connecting one Subrack in a frame to another Subrack in another frame) both ends of the trunk cable will be terminated with Male MPO connectors. In this case you will also need female to female MPO Loop back Polarity A.