Corning, OFS, and Prysmian all offer 20,000-foot reels for loose-tube cables in this fiber count range. Some will go to 25,000 feet on request for 12F, though you'll pay a premium for the larger reel and may face delivery logistics headaches if the staging area is tight. Plan fiber optic cable reel lengths around the actual route, installation method, splice locations, handling limits and delivery conditions—not total project quantity alone. I've seen it happen on FTTH builds in rural Mississippi, on middle-mile routes through the hill. Fiber optic cables can be custom cut by Proterial Cable America or distributor to match your required lengths for each cable run.
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