Protector PVC Perchloric Acid Laboratory Hood. 37.7" deep. Features heat-welded unplasticized PVC liner, built-in washdown system, integral work surface, drainage trough and 3/16" thick tempered safety glass vertical-rising sash with frame of powder-coated aluminum and PVC (glass is suitable for perchloric acid use). May be thoroughly rinsed after each use to prevent the acumulation of potentially reactive perchloric salts. By-pass airflow design.