Fiber optic conduits are received around a central axis with their axes extending in the same direction as the central axis and with each fiber optic conduit tangent to two other fiber optic conduits. The fiber optic conduits define a first interstitial space therebetween and a plurality of second interstitial spaces between each pair of fiber optic conduits on a side thereof opposite the first interstitial space. An interstitial member is received tangent to each pair of fiber optic conduits defining each second interstitial space. Grounding members surround the interstitial members and the fiber optic conduits with their longitudinal axes extending in the same direction as the central axis. Each grounding member is tangent to two other grounding members and an imaginary tube which surrounds and is tangent to the interstitial members and the fiber optic conduits and which has a longitudinal axis coaxial with the central axis.