Air Science, P5-24, Ductless Fume Hood, 24W x 31.5H x 26.5D, With Free Air Science Carbon Filter, ASTS-001, 18W x 2"H x 18"D. Purair® Basic ductless fume hoods offers features that are very important in terms of safety that are not found with any other competitive products. Basic fume hood requires one Carbon or HEPA filter (Carbon Filter Included). The Purair® Basic Series ductless fume hoods are a series of high efficiency fume hoods designed to protect the user and the environment from hazardous vapors generated on the work surface. WARNING: At least one filter must be ordered separately from the fume hood and is a required accessory. Special purchase now includes free General Purpose Carbon Filter (a $180 value) part number ASTS-001 / WBM1170706 for ductless fume hood. GP Formula for solvents, alcohols, odors, hydroCarbons. For Acid vapors please order fume hood filter part number ASTS-015 / WBM1170708 ACI Carbon Filter. For Formaldehyde vapors please order fume hood filter part number ASTS-013 / WBM110709 FOR Carbon Filter. For POWDER application please order a HEPA filter ASTS-030 / WBM1170707. NOTE: up to two filters can be stacked in this fume hood for multiple applications. Purair fume hoods are UL61010 listed.