These models are used extensively in heat treatment/drying or burn-in of semiconductor wafers, liquid crystals, disks and other components and devices requiring clean air conditions. These units can also be prepared for installation in clean-room environments. Class 100 cleanliness is achieved by employing a HEPA filter and a back-to-front laminar circulation system. The high-performance models (with MS suffix) provides stable performance even during heat-up or cooling.