This Forma 3033 Steri-Cult 200 CO2 incubator has a warm air jacket that ensures temperature uniformity throughout the chamber and minimizes condensation on the inner door. Sterile HEPA filter (99.7% retention at 0.3 microns) continually returns contaminant-free air to the chamber atmosphere, thus protecting chamber contents. (IF YOU DO NOT NEED STERILE AIR, YOU CAN USE THIS UNIT WITHOUT CHANGING/USING THE HEPA FILTER). Interior glass door, no adjustable shelves are included, but may be available from stock at an extra charge. Temperature range: 4C above ambient to 45C. CO2 range: 0-20%. Humidity and temperature control (relative humidity: ambient to 95% at 37C). Chamber capacity: 10.5cu.ft. The effective humidity range can be set and controlled from 70% to 98% RH in 1% increments. ***can also be used as a regular incubator or humidity chamber without connecting CO2*** This incubator was made in 1996.