Featuring CO2 and temperature uniformity, the SHEL LAB Model 2428H includes a user controllable humidity system that is more responsive to door openings than a traditional water pan humidity system. It provides less evaporation of culture media and eliminates a potential source for contamination and has a heated glass door that minimizes condensation, another potential source for contamination. This triple-paned glass door allows easy viewing of samples without having to open the incubator door, so samples can thrive in the stable environment within the chamber. It uses a gentle horizontal air flow heating system to obtain temperature uniformity and quick temperature recovery after door openings.