Abstract: A splice sleeve to protect fused or jointed optical fibers at and adjacent their point of fusion against environmental damage and to restore adequate strength by creating a suitable reinforcement at the splice after the fusion. The splice sleeve preferably includes an inner tube, a strengthening rod, an outer tube, and an activatable heat source including one or more substances. Preferably, the strengthening rod and the heat source are disposed between inner tube and outer tube. In use, the splice sleeve is positioned over the point of fusion of the fibers. The substances are exposed to each other, preferably inside of the heat shrinkable tube. This produces a chemical reaction that gives off heat sufficient to affix the splice sleeve to the fused fibers and reinforce the fibers at their point of fusion.