The Multimode (MM) Fibers are available in Graded Index (GRIN) and Step Index (SI) for a variety of core and clad sizes. The GRIN fibers range from 50um and 62.5um germanium doped cores to very large core fibers – 200um through to 800um cores. The SI fibers are offered in the large core fiber sizes but can be specially ordered with 50um and 62.5um core variants. Fibercore also offers a specially designed GRIN fiber with a 50um core that is suitable for long term use in downhole hydrogen environments as experienced in the Oil & Gas industry. Contact Fibercore for further information.