The Alto 4101XL case has a shell made with the Bam Hightech technique: a triple-ply structure made of high performance materials (ABS, Airex foam or PVC foam, another type of ABS) ensuring outstanding protection and ultra-light weight. The Inside cradle made of high-density polyurethane foam, injected around a mold taking on the exact shape of the instrument and protecting it against thermal shocks. Has 2 comfortable neoprene anti-slip backpack straps with removable security screw hooks.