KB "Belly Guides" have become a household word since their introduction with the original K-Series family. Fuji research noted that choke guide stresses at the mid-rod position were higher than at any other point along the runners of a loaded blank. To solve the problem, they developed a guide that exactly matches the standard KT runner yet has a much wider foot with two "locking arrows" designed into the foot. Baitcasting set-ups test stronger with 2 or 3 KB guides from the choke guide forward, while spinning rods need 1 maybe 2.