Measuring 3¾ in. wide, Unitary Wheel Cassette Series features corrosion-resistant, proprietary desiccant that is applied to lightweight all-aluminum wheel substrate. Honeycomb matrix's fluted opening design efficiently produces maximum latent and sensible air-to-air heat transfer. Besides assisting buildings in surpassing ASHRAE 90.1 building energy compliance, aluminum wheels can withstand temperatures of up to 180°F. Wheel diameters include 30, 36, 41, 46, 52, 58, 64, 68, and 74 in.