12-fiber MT-MT patch cords used in the parallel fiber optic module(QSFP+SR4) the connection to the optical lens and External Port. We use low loss MT Ferrule, Corning Clean Curve OM2 or OM3 fiber to achieve low attenuation. Total length’s tolerance ±0.15mm, MT Ferrule’s tolerance ±0.05mm, are available to satisfy coupling in small space of the module.