For use with older models of Protector Premier, XL Benchtop, Stainless Steel Radioisotope and Stainless Steel Perchloric Acid Fume Hoods made before 2012. A Sash Stop restricts how far a vertical-rising sash may be opened. This small plastic device may be easily field installed on the fixture panel of a Protector Hood, which have been factory-prepared to accommodate a sash stop at the 60% open position (18 in. to work surface). Alternate sash positions may be field drilled. Each Sash Stop Kit includes components for one sash.