The sheath is the unique, patented idea that allows the Equalizer® Express® to use a flexible blade and still have the strength to cut the toughest urethane. The sheath is a protective sleeve that surrounds the blade so the blade will not damage the dash or garnish mouldings or headliner. Express® blades come in longer and shorter sizes, but there is only one size sheath and it fits all Equalizer® Express® tools. Made in USA.