This loopback adapter by Delock can be used for testing purposes and for testing fiber optic connections. With the loopback, the transmission capability of the optical fibers can be measured. Specification https://elecena.pl/product/18568754/86930-fiber-optic-loopback-adapter-lc-om2-multimode-beige 2021-05-24 https://elecena.pl/product/18568754/86930-fiber-optic-loopback-adapter-lc-om2-multimode-beige 2021-11-05