The new 400 denier nylon bladder has a tighter weave and is therefore more puncture resistant than a broad weave. The Explorer's 1680 ballistic nylon outer shell is designed for maximum abrasion resistance. Heavy-duty zipper has a three-inch wide strip of Cordura to prevent zipper chaff on the inner bladder. Two-inch webbing-reinforced backbone construction. "Trap-door" drainage system allows water to drain rapidly from the outer cover to minimize excess weight and diver effort reboarding the dive boat. Inflator elbow strain relief constructed from two-inch nylon webbing minimizes wear on this connection. Narrower, elongated construction improves streamlining and trim. Relocated corrugated hose eliminates stress from impact with tanks. Halcyon inner bladders are RF welded with a lifetime warranty on all seams.