Cables must be covered to withstand adverse environmental conditions when used outdoors. Two, four, or six optical fibers are usually bundled in a cable with diameters between 5 mm and 10 mm. Numerous fiber combinations are possible.
Bundles of up to six LDFs with a PVC or LSZH fireproof cladding.
All step-index fibers with wavelength ranges from the UV to the near infrared can be bundled with a protective layer made of plastic.