This hood features one-piece shell molded of chemical resistant polyethylene. The inside corners are round. Clear acrylic panel slides inside tracks with stop pins. The front opening is 12"H x 22"W. Closed panel leaves a gap at the bottom for continuous air flow. Either 4 in or 6 in dia duct may be used. An exhaust system capable of drawing 200 cfm (free air) is recommended. The overall dimensions are 27"W x 13"D x 22"H. Ship wt is 38 lbs.