These are very useful in R & D /TESTING LABS. Where harmfulproduct is under testing to provide protection to product,operator and to environment . To achieve this these units are designed with utmost care. Negative pressure is maintained within the unit by exhausting 10% of air outside the unit.U.v. light provided to kill microorganism.Available in CLASS I, II, III of protection and CLASS 100( ISO-5) cleanliness. Standard size 3’x 2’, 4’ x 2’.other sizes can be made as per order.