Symphony air coolers use innovative Honeycomb and Aspen cooling pads. Honeycomb pads have a unique lattice structure that resembles a honeycomb. This medium provides a superior cooling effect due to the increased surface area for transfer of humidity in passing air. Aspen cooling pads are made from shredded aspen wood fibers that are held together in a pad structure. Aspen is a completely natural material that provides 75% cooling efficiency.Both Aspen and Honeycomb cooling pads are completely natural and highly cost-effective.