Laminated aluminum shims are designed to aid in the installation of Ruland manufactured zero-backlash jaw couplings. They come with 32 layers that can be peeled off with a knife or other sharp object. Each layer is .002" (.05mm) thick and made of 5052 aluminum for corrosion resistance, rigidity, and durability. Laminated shims ensure proper spacing between the hubs and inserts, allowing couplings to reach their full misalignment capabilities. The shim is simply slid into the space between the hub and insert while the user is tightening coupling hardware to its recommended seating torque and then removed once assembly is complete. All shims are manufactured by Georg Martin GmbH in Germany and are RoHS3 and REACH compliant.