So-Low HCN4-33 Humidity Stability Chamber / Refrigerated Incubator designed for precise humidity and stability, So-low Stability and Humidity Chambers are manufactured with a heavy duty double wall Interior and exterior. The cabinet and door are insulated and sealed with 100% UL Class 1 rigid polyurethane foam insulation, reinforcing the precision of stability within the chamber. Security and accessibility options are also available with a key lock door on the full length stainless steel pull handle, and 4" casters for trouble-free mobility. For storage, the 30 cu. ft. model includes three stainless shelves and an interior drain for user conveyance, while the 21, 48 and 76 cu. ft. models include three plated wire shelves per door.