An inflatable system includes a first bladder configured to contain gas and a second bladder configured to contain gas. The first bladder includes a top wall, a bottom wall opposite of the top wall, a sidewall extending between and connected to perimeter edges of the top and bottom walls, and a plurality of tethers extending between and connected to interior surfaces of the top and bottom walls. The second bladder includes a top wall, a bottom wall opposite of its top wall, a sidewall extending between and connected to perimeter edges of its top and bottom walls, and a plurality of tethers extending between and connected to interior surfaces of its top and bottom walls. The bottom wall of the first bladder is secured to the top wall of the second bladder.