A tool for inserting into a cavity is provided. The tool includes a plurality of segments moveably coupled to one another, each segment moveable relative to an adjacent segment between a bent position and a coupled position, the plurality of segments including a first segment, the first segment including: a core formed of a first material; and a shell formed of a second material and comprising or defining a guide feature, a drive feature, a line guide, or a combination thereof; wherein the first material defines a greater stiffness than the second material.