4" Doc’s® J-Hooks can hold up to 300 4-Pair UTP CAT 5e or 2-strand fiber optic cables; or up to 220 CAT 6 cables. Doc’s® J-Hooks will support all types of data comm and low voltage cables, such as CAT 5, CAT 5e, CAT6, CAT 6a, CAT 6e, fiber optic, and innerduct. J-Hooks can be attached to a variety of structures.